Working with Decimals

1. Working with Decimals Summer Packet Review

2. Adding & Subtracting Decimals • To add decimals, follow these steps: • Line up the decimals 2) Put in zeros so the numbers have the same length 3) Add or subract normally, remember to put the decimal point in the answer.

3. 1) 6.938 + 2.75 = ___________ 2)8.22 + 5.74 = ___________ 3)0.936 + 8.2 = ___________ 4)5.1925 + 3.564 = ___________ 5) 4.1 + 10.14682 = ___________ 6) 7.37 − 6.17 = ___________ 7) 5.687 − 3.34 = ___________ 8) 5.4 − 3.9 = __________ 9) 6.935 − 5.44 = ___________ 10) 6.3 − 1.69 = ___________

4. Multiplying Decimals 1) Multiply the numbers just as if they were whole numbers. • Line up the numbers on the right - do not align the decimal points. • Starting on the right, multiply each digit in the top number by each digit in the bottom number, just as with whole numbers. • Add the products. 2) Place the decimal point in the answer by starting at the right and moving a number of places equal to the sum of the decimal places in both numbers multiplied.

5. 0.1 × 0.09 = _______ 0.04 × 0.1 = _______ 0.7 × 0.9 = ________ 0.4 × 0.2 = _______ 4.6 × 0.1 = _______ 2 × 0.7 = _______ 9.466 × 0.10 = _______ 3 × 0.71 = _______ 7 × 0.162 = _______ 2.5 × 0.79 = _______

6. Dividing decimals • The first important thing about dividing decimals is knowing how to write the problem in the first place! If you see a problem like the one below, the first number goes inside the divisor and the second number goes on the outside! Once the problem is written correctly, the four steps for dividing are: • 1. Move the outside decimal all the way to the right • 2. Move the inside decimal to the right the same number of places as the outside decimal was moved • 3. Raise the inside decimal straight up • 4. Divide 3.16 ÷ 0.4 0.4 3.16

7. Examples: • 1) 10.5 ÷ 5 • 2) 15.12 ÷ 2.4 • 3) 0.45 ÷ 0.05 • 4) 0.015 ÷ 0.3 • 5) 0.427 ÷ 0.7