Hot Math How-Tos
How To: Find the median of a set of numbers
This is a how-to-video which demonstrates techniques to find the median of number in a series. This demonstration takes the following example.
How To: Add fractions with mixed numbers using math
When you start out using fractions, one of the first things you will learn is how to add and subtract them. In this tutorial, made specifically for beginners, you will learn the basics of adding fractions with mixed numbers. This is really not very hard and if you follow along with the step by step presented in this tutorial, you will have the hang of it in no time. Once you master this step, you will be well on your way to an A in your math class!
How To: Add or subtract fractions with different denominators
In this tutorial, you will learn about fractions. Fractions may look scary, but they are relatively easy to handle if you take your time. In this particular video, learn how to add or subtract fractions that have different denominators. You will learn how to reduce common fractions to the lowest common demoninator in order to fit them into your equations and how to find the answer.
How To: Calculate probability in "at least one" problems
Calculating probablities can be used to help us make decision. PatrickJMT explains how to calculate probability in an "either A or not A" scenario. The probability of A plus the probability of not A is equal to one. Therefore, the probability of A is equal to one minus the probability of not A ; P(A)= 1 - P(not A). The probability of a major earthquake in San Francisco over a period of time is used as an example. The probablity of an earthquake of a magnitude of 7.5 or greater in San Francisc...
How To: Find the entire length of a segment using the midpoint
This video shows the method to find the length of the total segment using the midpoint. Let the total line segment be PS. Let Q be the midpoint of PS. Let R be a point on the line segment QS. The first step involves the use of midpoint to find out the length of QS. We are given that QR = 1 and RS = 4.5. QS is equal to QR plus RS which is equal to 5.5. Now since Q is the midpoint of PS the total length of the segment PS is equal to twice the length of the segment QS. This is equal to 11 units....
How To: Find the length of a segment using the midpoint II
First of all in the given question you have to write down the values of the total length of the line segment, PS=15. The length of the line segment, QR =3. Now you have to find the value of line segment RS. Because you know that the Q is the midpoint of the line segments PQ and QS must be equal. Therefore you can find out the length of the half of the segment using the midpoint. Subtract the value of QR from QS. Given that segment PS=15 and Q is the midpoint, you can conclude segment PQ=7.5 a...
How To: Work with decimal numbers in prealgebra
You can do simple decimal calculation with out using a calculator once you understand the basic concept of decimals. In decimal equations when you have various operations between decimal numbers, you have to go by the order of operations in simplifying it. The order of operations states that you have to first divide, then multiply and at last add or subtract the remaining terms. You have to work the operations from left to right. Use a calculator only when you are required to multiply or divi...
How To: Change improper fractions into mixed numbers
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this free math tutorial, you'll learn how to change top-heavy improper fractions into mixed numbers.
How To: Graph linear equations using a table
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this free video math lesson, you'll learn how to graph a system of linear equations using a T-Chart.
How To: Graph x & y intercepts on a TI-84 Plus calculator
In this video the teacher shows us how to use a TI-84 plus graphing calculator to graph a function, adjust the view window, and determine the values of several types of critical points on the graph such as x-intercept, y-intercept, local maximums, and local minimums. After entering the function in the Y= editor she presses the ZOOM button and selects Z-Standard this adjusts the view window to a range of -10 to 10 on both axis. To find each of the critical points requested the teacher uses the...
How To: Use differentiation equations to solve for position
This video teaches how to use calculus find the position, velocity and acceleration of an object. Imagine an object moving on a straight line. It's position at any time (t) is given as s(t) pronounced "s of t". It's velocity is v(t)= s'(t) which is the derivative of s(t). It's acceleration a(t) is the derivative of its velocity v'(t). If we look at it from a different perspective we are differentiating. The derivative of the position is its velocity, the derivative of its velocity is it accel...
How To: Find the average value of a function over an interval
When you have to find the average of two or five numbers then you have to add all the numbers and then divide then by two or five respectively. However in the case of the function you have infinite many values over any interval. But it is not possible to add all and then divide by infinity. Therefore you have to calculate in a different way. Imagine that you have to find the average of y=f(x). Then you have to average it from the interval from ‘a’ to ‘b’. The inner area under the curve shall ...
How To: Approximate the area under a curve using rectangles
The idea of finding the area under a curve is an important fundamental concept in calculus. Consider a function y = f(x). Now the area under the curve is to be calculated. The area under a curve problem is stated as 'Let f(x) be non negative on [a, b]. Find the area of the region lying beneath the curve y = f(x) and above the x-axes, from x = a to x = b. Note that finding the area under a curve will imply that you are dealing with a non negative function. The way to approach is to divide the ...
How To: Use a formula to find the area of a parallelogram
This video shows us how to use a formula to find the area of a parallelogram. The formula for finding the area of parallelogram is the same as finding the area of rectangle or a square which is equal to length time’s breadth. But the parallelogram looks a bit different and the parallelogram is basically a rectangle but it is not at right angles. If you draw two altitudes then it is a rectangle with two triangles and if you cut one of the triangles and paste it next to another triangle then we...
How To: Solve complex indefinite integrals in calculus
In this video the math teacher explains the meaning of the indefinite integral formula in calculus by stating it in terms of antiderivatives. He then shows in general terms how this indefinite integral formula has a related derivative formula, i.e. if the derivative of F(x) is f(x) then the indefinite integral of f(x) is F(x) plus a constant term (C). With this general relationship the teacher takes us through three related examples where he converts a derivative formula to an integral formul...
How To: Antidifferentiate functions with radicals in calculus
This video demonstrates how to do anti-differentiate functions with radicals in calculus. To simply problems, try to substitute. For example, in the problem, the integral of x times the square root of x plus 2 dx. You can substitute w for everything underneath the radical: i.e. x + 2. When you simplify, it becomes: the integral of x times the square root of w dw. Now, you need to get rid of the x, which you can do with a substitution: w – 2 = x. Now, plug in the values and simplify it.
How To: Find density using the water displacement method
To find out the density of any given object there is a simple equation, mass divided by the volume equals the density. In this video a lady is showing how to get the volume of three objects using water. First the objects are measured on a scale to find out how much they weigh, the mass. Next each one of the objects is placed into a measured amount of water to find out the volume. Before you place the object into the water you will want to know just how much water in there. That way when the o...
How To: Cancel out in basic algebra
This video gives you brief tutorial on simplifying expressions, or canceling out common factors. He starts out by answering the question "What is canceling?" and demonstrates a basic example. You find the greatest common factor between the numerator and denominator, which you then divide both by. This can also be done if you have variables in your fraction. He then shows it can be done the same way if you have binomials in your fractions. However, you must be careful that the denominator does...
How To: Find the graph of a square root function
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to sketch the graph a square root function.
How To: Use the quadratic formula on a graphing calculator
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to work with the quadratic formula on your graphing calculator.
How To: Divide decimal numbers by whole numbers in basic math
Your first step is to bring your decimal point up to the top of the equation. The you divide the whole number into the decimal number. In this instance, 5 into 1.25. 5 goes into 1 0 times, so you put the zero in the first space. 5 goes into 12 twice, so you place a 2 up top, after the decimal. Then you subtract 10 from the 12 to leave you with a 2. This then gets added on to the 5, so you divide 2 into 25 giving you 5. So your answer is 0.15. You can then do this for any whole number and frac...
How To: Rationalize a denominator
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to rationalize a denominator.
How To: Make calculations with the Pythagorean theorem
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to solve problems with the Pythagorean theorem in geometry.
How To: Solve a complicated radical equation in algebra
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to solve a complex radical equation in algebra.
How To: Chart data with a box and whisker plot
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free statistics tutorials, you'll learn how to use visualize data by graphing it in a box-and-whisker diagram.
How To: Measure dispersion with range, variance & std dev
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to use statistical range, variance and standard deviation to measure dispersion in a data set.
How To: Solve rational equations in algebra
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to solve an equation in which to rational expressions are said to equal each other.
How To: Add rational expressions in algebra
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework). With this three-part installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to sum rational expressions in algebra.
How To: Simplify rational expressions in algebra
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this two-part installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to simplify rational expressions in algebra.
How To: Graph radical functions in college algebra
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just study for that next big test). With this two-part installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to graph a rational function in college-level algebra.
How To: Find the asymptote of a rational function in algebra
From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to calculate the asymptote of a rational function in college-level algebra.
How To: Solve math problems using proportions
Proportions or ratios are fundamental concepts of mathematics. A proportions is an equation that states that two ratios are equal. Hence proportion can be written in two ways as a:b=c:d or a/b=c/d. In these equations a and d are called as extremes and b,c are called as means. So when working with proportions we can state that product of the means is equal to the product of the extremes i.e. a*d = b*c. This is obtained by cross multiplying the second form of proportions. In mathematics you are...
How To: Find the circumference of a circle using basic math
This video teaches us the method to find the circumference of a circle given its radius. The video tells us to find the answer in terms of pi and also to the decimals value. The formula to find the circumference is two times the product of pi and the radius. The first step involves the drawing the circle and marking the radius. The radius of the circle in the video is 6.5 cm. Now use the formula to find the circumference. Substitute the value of the radius in the formula of circumference. We ...
How To: Figure out the area of quadrilaterals
Quadrilaterals are four sided shapes that are closed. They are polygons. Quadrilaterals can be classified broadly in two ways. If the quadrilateral has a two pair of parallel sides then it falls in to the parallelogram category. Further now it can be broken down in to other shapes like square, rectangle, rhombus. If it has only one pair of parallel side then it falls into the trapezoid category. To compute the are of a trapezoid first you need to know the lengths of the parallel sides. Add th...
How To: Solve for x in the algebra equation -7 + 13x = 58
In this video he just explained about how to solve an algebra problem. The problem is -7+13x=58. He just solve the problem in simple steps. First you find out the x in this problem. To find out x you just add 7 to each side. Then it will be -7+7+13x=58+7. Then the equation will be 13x=65 because in the left side of the equation -7 canceled by +7 so then the equation is 13x=65. Next you just add the divide by 13 each side of the equation. Then the equation will be 13x/13=65/13. Then 13 divided...
How To: Reduce fractions to their simplest form in basic math
This video teaches us the method to simplify the fractions. Let us take an example of 18/24. Find a number that goes into both 18 and 24. Divide the top and bottom by the same number. Here, 2 will go into both numbers. So, the number now becomes (18/2)/(24/2) which gives 9/12. This fraction can be further simplified by dividing the top and bottom by 3. We get 3/4 which is our final answer. The fractions 18/24, 9/12 and 3/4 are called equivalent fractions since they are of the same size. Simil...
How To: Quickly find the area of a trapezoid
In this video, Mr. Maisonet provides a quick and easy method for calculating the area of a trapezoid. In the first step, The lengths of the two bases (the two sides of a trapezoid that are parallel to one another) are averaged. The lengths of the bases are first added together, and the sum is divided by two, yielding the average. The average is then multiplied by the height. The resulting product is the area of the trapezoid. This method for finding the area of a trapezoid is mathematically s...
How To: Reduce a fraction by finding common factors in math
The aim of the video is to show how to reduce a fraction by factoring out prime numbers that are common to both the numerator and the denominator. The example shown in the video is 27/21. The number 27 can be achieved by multiplying 3 by 9 and the number 21 is the result of 3 multiplied by 7. The common factor, therefore in both the numerator and the denominator is 3. 3 on the top divided by 3 on the bottom is 1 and so this can be removed without affecting the value of the fraction, leaving 9...
How To: Easily find the area of a rhombus
In this video, you will learn how to find the area of a rhombus. The formula is A = 1/2 d1 * d2. The d1 is the diagonal inside the rhombus, while d2 is the other diagonal inside the rhombus. You will need to find the length of these lines in order to complete the formula. For example, if one length is 5 and the other is 4, then you should plug in the numbers into the formula. This will equal 20 divided by 2, or 10. 10 units squared is the answer to this particular problem. Viewing this video ...
How To: Find the area of quadrilaterals
Parallelogram is a quadrilateral in which both pairs of the opposites are parallel. To find the area of a parallelogram first draw the diagram of a parallelogram. Parallelogram can be further divided into squares and rectangles. To calculate the area of both of these kinds of parallelograms multiply the length of the parallelogram with its height. In general the area of a parallelogram in obtained by multiplying the base of a parallelogram with its altitude. In square and rectangle cases, the...