Multiplying and dividing decimals

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The importance of multiplying and dividing decimals

The importance of knowing how to multiply and divide decimals are an important life skill that you need to learn. It helps you in many different ways in life. paying taxes is something you do almost everyday wether you are buying food or eating out at a resturant. Taxes are 8.25% of the money you pay. When you figure out how much a tax is, you have to multiply the price with 8.25. You need to know how to multiply decimals to know how to do that. Also when your building a building and you need to know the width of it, but you only know the area and length , you need to divide the area and the length to figure out the width.

Steps to dividing decimals

The first step is to move the decimal o the divider how much times to make it a whole number. You move the decimal how much times you moved it on the divisor. Than you do regular division ignoring the dividends decimal. (if it even has one.) you find out the answer and move the dividends decimal straight up without moving it.

multiplying and dividing deciamls video

Multiplying Decimals

To multiply decimals:

  1. Ignore the decimal points and multiply as you would whole numbers.
  2. Count the number of decimal digits (the digits to the right of the decimal point) in both of the numbers you multiplied.
  3. Beginning at the right side of the product (the answer), count left that number of digits, and put the decimal point to the left of the last digit you counted.

Example: 1.57 × 2.4

1.Multiply 157 times 24: 3768

2.Because there are a total of three decimal digits in 1.57 and 2.4, count off 3 places from the right in 3768 and place the decimal point to the left of the third digit you counted (7):

To check the reasonableness of your work, estimate the product by using the rounding technique you learned in Lesson 6. Round each number you multiplied to the nearest whole number, and then multiply the results. If the product is close to your answer, your answer is in the ballpark. Otherwise, you may have made a mistake in placing the decimal point or in multiplying. Rounding 1.57 and 2.4 to the nearest whole numbers gives you 2 and 2. Their product is 4, which is close to your answer. Thus, your actual answer of 3.768 seems reasonable.