Add Decimals Videos - Free Educational Videos for Students in K - 12

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This page provides a list of educational videos related to Add Decimals. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Add Decimals.


Adding and Subtracting Decimals


By TeacherTube Math

This video is from the TeacherTube website and the instructor shows how to add and subtract decimals. She shows how to line up the decimal points in the numbers. Instructor appears to be using computer software for demonstration.

Multiplying decimals 3


By Khan Academy

Multiplying decimals? Try multiplying without the decimals first, them add them back in. We'll show you.

Multiplying decimals 2


By Khan Academy

Multiplying decimals? Try multiplying without the decimals first, them add them back in. We'll show you.

Subtracting decimals 2


By Khan Academy

Just like when add, be sure you align decimals before subtracting.

Math Ratios | MathHelp.com


By MathHelp.com

This lesson covers adding decimals. Students learn to add decimals by first lining up the decimal points, then adding the numbers by column. For example, to add 14.2 + 2.86, first line up the decimal points, then add the digits in the hundredths column, to get 0 + 6, or 6, then add the digits in the tenths column, to get 2 + 8, or 10, so write a 0 in the tenths column and carry the 1 to the units column, then add the digits in units column, to get 1 + 4 + 2, or 7, then add the digits in the tens column, to get 1. So 14.2 + 2.86 = 17.06.

Dividing decimals 1


By Khan Academy

Sometimes, in order divide numbers completely you have to add a decimal and bring down places. Let's do it together, shall we?

Dividing completely


By Khan Academy

Sometimes, in order divide numbers completely you have to add a decimal and bring down places. Let's do it together, shall we?

Adding Decimals | MathHelp.com


By MathHelp.com

MathHelp.com offers is your complete solution for understanding Geometry. We offer a custom Geometry course as well as custom courses for over 100 standardized tests, including COMPASS, ASVAB, ACCUPLACER, PRAXIS, SAT, GED, GRE, and many more.

Multiplying Scientific Notation | MathHelp.com


By MathHelp.com

In this example, which involves natural logarithms, we’re asked to solve each of the following equations for x, and leave our answers in terms of e. To solve for x in the first equation, ln x = 3, we simply switch the equation from logarithmic to exponential form. Remember that ln x means the natural logarithm of x, and a natural log has a base of e. So, to convert the given equation to exponential form, remember that the base of the log represents the base of the power, the right side of the equation represents the exponent, and the number inside the log represents the result, so we have e…to the 3rd…= x, and we’ve solved for x. Notice that our answer, e cubed, is written in terms of e, which is what the problem asks us to do. Now, let’s take a look at the second equation, ln x squared = 8. Again, we solve for x by switching the equation from logarithmic to exponential form. Ln x squared means the natural logarithm of x squared, and a natural log has a base of e. So, converting the equation to exponential form, we have e…to the 8th…= x squared. Next, since x is squared, we take the square root of both sides. On the right, the square root of x squared is x. On the left, however, there are a couple of things to watch out for. First, remember that the square root of e to the 8th is the same thing as e to the 8th to the ½, which simplifies to e to the 8 times ½, or e to the 4th. Also, remember that when we take the square root of both sides of an equation, we use plus or minus, so our final answer is plus or minus e to the 4th = x.

Dividing Scientific Notation | MathHelp.com


By MathHelp.com

To multiply numbers that are in written in scientific notation, such as 1.4 x 10 to the -2nd times 5.3 times 10 to the 6th, we first multiply the decimals, in this case 1.4 times 5.3, to get 7.42. Next, we multiply the powers of 10, in this case 10 to the -2nd times 10 to the 6th. Notice that we’re multiplying two powers that have like bases, so we add the exponents and leave the base the same, to get 10 to the -2 + 6, or 10 to the 4th. So we have 7.42 times 10 to the 4th. Finally, we’re asked to write our answer in scientific notation. Notice, however, that 7.42 times 10 to the -4th is already written in scientific notation, because we have a decimal between 1 and 10 that is multiplied by a power of 10. So we have our answer.

Adding/Subtracting Decimals


By Mathademics

Adding/Subtracting Decimals