Active Math Posts

How To: Calculate standard deviation with graphing calculator

This video tutorial is in the Education category which will show you how to calculate standard deviation with TI graphing calculator. First you got to enter the data in to the calculator. Go to stat and click on enter. This will edit a list. Now you type in these numbers: 50, 20, 33, 40 and 55. Then press stat and click on enter. This will bring up the 1-var stats page. Press the "2nd" button and L1, because all our data is in L1. Click on enter and you will get all the data that you will nee...

How To: Find the determinant & area of a parallelogram

In this video, we learn how to find the determinant & area of a parallelogram. The determinant of a 2x2 matrix is equal to the area of the parallelogram defined by the column vectors of the matrix. Graph both of the equations that you are given on the vertical and horizontal axis. After you have all of the coordinates in place, you will be able to plug in the correct numbers to figure out what the answer to the equation in. This is more advanced math, so if you have not done it before, you sh...

How To: Find the area of a circle

In this tutorial, we learn how to find the area of a circle. The line from the middle to the edge of the circle is called the radius. Find what this is in your equation, then multiply (3.14 X radius x radius). This will always work out the area of a circle for you. So, do this equation with your calculator or by hand, then you will have the correct answer for the area. Make sure to add the units squared after you get the answer. If you are given the diameter (line all the way across), you wou...

How To: Divide and give an answer as a fraction

In this video we learn how to divide and give an answer as a fraction. If you are starting out with a simple fraction, you will simply take the number before the divide sign on the top and the second number on the bottom. If you end up with a number that is able to be simplified, make sure you take it down to it's most simple version possible. You can end up with a top heavy fraction, which means there will be whole numbers involved. Do the division to figure out how many times the bottom num...

How To: Multiply mixed numbers together

In this video we learn how to multiply mixed numbers together. First, take your mixed numbers and write them into an equation. Next, convert the numbers both to top heavy fractions. Now, multiply the top numerators together and then the denominators together. If you can't work out the numbers in your head use a method by writing it out in a table. As soon as you finish and end up with a final fraction, you need to simplify this. Find how many of each number goes into the larger one and then t...

How To: Subtract basic fractions in simple mathematics

This video tutorial is in the Education category which will show you how to subtract basic fractions in simple mathematics. You can do basic subtraction of fractions if the denominators are the same. If they are not, then find the lowest common multiple of the denominators and convert the denominators to their lowest common multiple. For example, to subtract 1/2 from 3/4 find the common multiple of 2 and 4, which is 4. So, the problem 3/4 - 1/2 can now be written as 3/4 - 2/4. Since, the deno...

How To: Add mixed numbers

A mixed number is just another way of expressing a fractional number. This video shows two methods by which two mixed numbers may be added.

How To: Convert top heavy fractions to mixed numbers

This is a video tutorial in the Education category where you are going to learn how to convert top heavy fractions to mixed numbers. Top heavy fractions are fractions with numerators greater than denominators. Mixed numbers are combination of whole numbers and fractions. To convert 12/5, find out how many 5s are in 12. The answer is 2 and after you remove two 5s from 12, you are left with 2. So, 12/5 is equal to 2 2/5. Similarly, in 10/3, you have three 3s in 10 and you are left with 1. So, 1...

How To: Change decimals to fractions

In this tutorial, we learn how to change decimals to fractions. First, you will take your decimal and put it over 1. Any number divided by 1 will be that number that you started with. To get rid of the decimal, you can multiply it by hand and moving the numbers to the left. To keep the number the same, you also have to multiply the bottom of the fraction by the same number. Now, you can just simplify the fraction and you will end up with the correct number! This is easy to do and is a great b...

How To: Graph & shade a polygon of constraints

This video shows us how to graph & shade a polygon of constraints. Start out by finding the non zero constraints and the other constraints and inequalities. You will need to know how to graph before you begin to do this equation. Look at the first constraint and then fill in the X and Y sign in your table. Continue on to do this for the other two constraints that you have. Once you have these written down and in front of you, it's just a matter of graphing. Start to graph with the given coord...

How To: Convert recurring decimals to fractions

In this video we learn how to convert recurring decimals to fractions. Start off by writing out the decimal with the dot next to it to show that it's recurring. This means that the number goes on forever and doesn't stop. To convert this to a fraction, write down the number as the numerator. On the bottom you will put the number 9 always. Now, you can divide these two numbers with each other using a calculator. Once you do this, you will get the correct answer. Once you divide it out, you wil...

How To: Understand the rule of vertically opposite angles

In this video we learn how to understand the Rule of Vertically Opposite Angles. This says that when two straight lines cross it produces vertically crossed lines that must have congruent angles. Because the lines are straight this has to happen. Remembering the rule "supplementary" you will be able to calculate the angle of A and B in the equation. Prove what each of the angles are using the different rules and then move onto the other two angles. Angle C can be figured out by knowing that i...

How To: Convert Fahrenheit to Celsius

In this tutorial, we learn how to convert Fahrenheit to Celsius. The equation that you will use to figure out Celsius is: C= F-32 (5/2). Once you do this, you can start to fill in the equation with the correct numbers that go in the spots. Continue to do this until you have reached the end of the equation. When you reach the end, you will have converted Fahrenheit to Celsius. This is a great way to convert temperature if you are traveling or following directions and need to convert these quic...

How To: Change fractions to decimals

In this tutorial, we learn how to change fractions to decimals. Once you learn how to do this, it can help you learn more levels of math. Start out with easy problems and work your way up to more difficult ones. First, try rewriting the equation. Take your top numerator and divide it out by hand by your denominator. After you have done the long math for this, the number that is on the top of the division sign will be your answer. You will need to have a good sense of what numbers add into wha...

How To: Divide & multiply fractions with numerous examples

In this video, we learn how to divide & multiply fractions with numerous examples. If you have a normal fraction, you will just multiply across the equation to multiply it. To divide the fraction, you will multiply it by the flip of the fraction. Once you do this, you will have both of these equations figured out. Make sure you reduce the fraction as much as possible by seeing what number goes into both the denominator and the numerator. After you do this, you will have the best possible answ...

How To: Convert Fahrenheit to Celsius for chemistry

This is a video tutorial in the Education category where you are going to learn how to convert Fahrenheit to Celsius for chemistry. Doing this is really simple and easy and doesn't take much time. But, you must know the formula for doing the conversion. The formula is degrees Celsius is equal to degrees Fahrenheit minus 32 divided by 1.8. Using this formula let us convert 75 degrees Fahrenheit to degrees Celsius. Inserting 75 in the formula, we get (75 - 32) divided by 1.8. and the answer is ...

How To: Add and subtract fractions with numerical examples

In this video, we learn how to add and subtract fractions with numerical examples. First, write down an example on a piece of paper to add two fractions together. To do this, you will write out the denominator in the common form and then add the numerators together. If you don't have common denominators you will have to find them. When subtracting, it's basically going to be the same process. Go through the same steps to figure out what the answer will be. Use the basic rules of math to get t...

How To: Understand and determine equivalent fractions

In this video, we learn how to understand and determine equivalent fractions. If you have an equation with an equivalent fraction, you will first multiply the first numerator by the second denominator. Then, you will divide this answer by the denominator of the first fraction. After you do this, it will give you the correct answer. You can also do the reverse multiplication for this to check your answer and make sure you are correct. You can get an answer no matter what the numbers in the equ...

How To: Find the area of a trapezoid

In this video, we learn how to find the area of a trapezoid. The formula to figure out how to find the answer is: Area= 1/2x (base1 x base2) x height. Now, find the bases and the height of the trapezoid. Remember that the height must always be perpendicular to the bases. Once you have found these, add the bases and multiply by the height. You can use a calculator to do this or do it off hand if you're good with math. For the third step, divide the answer by 2 and then write down the answers w...

How To: Find the surface area of a cube

In this video, we learn how to find the surface area of a cube. Finding the surface area of a cube is something everyone will have to do in math. The easy formula to figure out this is: surface area= side x side x 6. Your first step to figuring out the problem is to find the length of a side. Once you have found this, you will substitute and evaluate the numbers in the equation. After this, write the units in for the problem. You will then come up with the answer of the equation with the unit...

How To: Divide numbers with exponents

In this tutorial, we learn how to divide numbers with exponents. The quotient rule states that we can divide two powers with the same base by subtracting the exponents. With the same base, you can subtract the exponents to get something that would be the answer. For example, if you have 6(to the fourth) divided by 6(to the second), this would come to equal 6(to 4-2). This would break down to equal 6(to the second power). Once you have this, you will be able to do the math for this and figure ...

How To: Understand the properties of a rectangle

In this tutorial, we learn how to understand the properties of a rectangle. A rectangle has four interior angles that add up to 360 degrees. All of the angles have to be exactly 90 degrees in a perfect rectangle. Two opposite sides have to be congruent and parallel. The other opposite sides also have to be congruent and parallel. The diagonals of the rectangle are not perpendicular but they are congruent and they intersect at the mid points. Diagonals are not perpendicular, but they are congr...

How To: Solve inequalities by multiplying or dividing

In this tutorial, we learn how to solve inequalities by multiplying or dividing. Start out with your equation written out in front of you. Now, find the variable in the equation and figure out how to get rid of the denominator underneath it. Divide this on both sides, then you will be left with the variable with the inequality. Don't flip the inequality if you don't divide by a negative on both sides. Then, write out the rest of the equation. Once finished, do the rest of the math for the rig...

How To: Understand fraction multiplication by drawing

In this tutorial, we learn how to understand fraction multiplication by drawing. Start out by drawing a square on a piece of paper, leaving space around it. Next, cut this into vertical thirds (your equation is 1/3 x 1/2). After this, shade one of the thirds in the square. Use the side of your pencil to shade in the third. Then, cut the square into horizontal halves. The square will now be in equal shapes that are also called sixths. After this, shadow one of the halves with a different color...

How To: Understand special quadrilaterals

In this tutorial, we learn how to understand special quadrilaterals. A quadrilateral is a shape with four sides. Three figures of these are: kites, parallelograms, and trapezoids. Two types of parallelograms are the rhombus and the rectangle. Rectangles have four right angles. A square is also a parallelogram, which has four right angles and two congruent sides. A square is always a rhombus a parallelogram is always a quadrilateral and a kite is always a quadrilateral. The parallelogram is so...

How To: Master inverse proportions in algebra

This is a video tutorial in the Education category where you are going to learn how to master inverse proportions in Algebra. Inverse proportions have a different rule; more means less or less means more. Let us understand this with an example. It took 175 minutes to drive to the cottage at 80 kmph. If we drive at 100 kmph instead, how long will it take? Here the speed of travel is more but the time taken to complete the journey will be less. So, this is a more means less kind of inverse prop...

How To: Determine if a point lies on a line in standard form

In this video, we learn how to determine if a point lies on a line in standard form. In order to do this, you will need to substitute the X and Y value with the ordered pair that is given. The X value is the first number and the Y value is the second number. Re-write your equation, substituting in the numbers to the appropriate spots. Now, simplify the equation by doing multiplication with the negatives and positives (if given). When you get through the equation, you will end up with the solu...

How To: Borrow and regroup in math

In this video, we learn how to borrow and regroup in math. First, look at the top numbers of the subtraction equation. Look to see if it's smaller than the bottom number. If not, look at the numbers to the left of each one on the top to see if you can borrow from them. If you can, then you will have to lower than number by one each time you are borrowing a number. Once you do this, you will be able to subtract the number at the top from the number at the bottom, even when the individual numbe...

How To: Derive and use the slope formula

In this video, we learn how to derive and use the slop formula. The slope of a line is equal to change in y divided by the change in x. First, put the first point on the coordinate point. Then, represent the X and Y by X1 and Y1. Then, put the second point on the plane, representing the coordinates with X2 and Y2. Now, with these two points, draw a straight line and derive the formula from here. The change in X will be from X1 to X2. Now, replace that with the change in X and do the same for ...

How To: Multiply & divide fractions & mixed numbers

In this tutorial, we learn how to multiply & divide fractions & mixed numbers. When multiplying and dividing fractions you don't need a common number, you just multiply straight across. When dividing, you simply flip the second fraction over and multiply straight across like normal. When multiplying a whole number and mixed number, simply put the whole number over one. Then, convert the mixed number into an improper fraction. Then, multiply the mixed number with the numerator and add in the d...

How To: Find the area of a circle

In this tutorial, we learn how to find the area of a circle. First, you will need to know the formula for finding the area of a circle, which is Area=Pi(r)squared. Now, find the radius of the circle in question. After this, fill in the radius to the equation and start to do the math. The area will equal what the radius is, times pie and squared. After you do the math for this, you will have found the area of the entire circle. Make sure you label the number with units, or else your answer wil...

How To: Solve rational inequalities

In this video, we learn how to solve rational inequalities. First, you will take the problem (x-1 over x+2 is greater than 0). The first method to solve this is to think you have any number divided by another number is greater than 0. Remember the properties to solving problems. Know that both A and B have to be greater than 0 since it's a positive divided by a positive. Or, you can have a negative divided by a negative which will make a positive. The first solution is (x-1 greater than 0 and...

How To: Multiply fractions

In this tutorial, we learn how to multiply fractions. First, you must know that the number on the top is called a numerator and the number on the bottom is the denominator. First, write out your equation with the fractions listed horizontally next to each other. After this, multiply the numbers straight across. The numerator will multiply with the numerator and same for the denominator. After this, when you get the final fraction you will need to reduce this further if you can. If you end up ...

How To: Solve a single-step equation using multiplication

In this video, we learn how to solve a single-step equation using multiplication. For the first step, get rid of any number surrounding the variable. To do this, you will need to multiply the numbers around it by their opposite to make them equal zero. Once you have done this, you will need to repeat the process on the other side of the equal sign. Just do the same exact thing you did in the first step, then you will be able to easily solve the problem at hand. You can check your answer by re...

How To: Grasp the differences of census, study, & sample survey

In this tutorial, we learn how to know the difference: census, study, & sample survey. The census is when everyone's opinion is needed. An example is when you will see census studies happen throughout the year from the government seeing how many people live in one household. A study is when you only need the opinion of experts. This can be when companies are releasing a new product and need the opinions of doctors or dentists about it. A sample survey is when a few people's opinions are enoug...

How To: Bisect a line segment

In this tutorial, we learn how to bisect a line segment. First, you need to adjust your compass so the distance from the sharp part and the drawing part is the size of the line. Then, put the sharp part on one side and draw your arc with the pencil. Do this on both sides of the line so your image shows two arcs that intersect each other. Since you have these two intersecting lines, you can draw a line between these to show where the middle of the line would be. Use a ruler to draw this straig...

How To: Find the volume of a pyramid

In this tutorial, we learn how to find the volume of a pyramid. The equation to figure out how to find the volume of a pyramid is 1/3ab x h. When you begin, find the height, length, and square feet of the pyramid, then fill these into the appropriate spots in the equation. Once you find this, you will be able to find the correct number of the volume of the pyramid. After this, make sure you have the correct labels on the answer that you get from the equation you filled out. When finished, you...

How To: Identify the constraints & function to be optimized

In this tutorial, we learn how to identify the constraints & function to be optimized. When you are asked for the elements of constraints, you are being asked for the plain English version. If you are told you only have so much of something inside of a written problem, then take into account all of the limits that are listed. Once you have these, write them down so you have them in one place. After this, write down the number for the unrestricted part of the problem. After this, you will be a...

How To: Write equivalent fractions

In this tutorial, we learn how to write equivalent fractions. If you have a negative in front of the fraction, it's the same as writing the negative on the numerator or the denominator. If we would have a negative on the top and on the bottom, this would cancel both out to create a positive, which wouldn't be right. To write the fractions, simplify it. If it's already simplified, you will need to multiply the fraction. After you do this, you will finish the equation and have it written out in...