# FRACTIONS & DECIMALS How to add, subtract, multiply, & divide fractions and decimals.

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FRACTIONS & DECIMALS How to add, subtract, multiply, & divide fractions and decimals.

FRACTIONS : ADDITION 1.Rewrite fractions with common denominators a. If you have a mixed #, rewrite the whole # in front of the “new” fraction with the common denominator. b. If you have a whole #, rewrite the whole number and write the fraction as 0 over the denominator of the fraction. 7/12 + 3/4 = 7/12 + 9/12 = 16/12=1 1/3 2. Denominators stay the same 3.Add numerators 4.Add whole #’s 5.Simplify a. Rewrite improper fractions as mixed numbers b. Divide by common factors to simplify fraction s

FRACTIONS: SUBTRACTION 1.Rewrite fractions with common denominators a. If you have a mixed #, rewrite the whole # in front of the “new” fraction with the common denominator. b. If you have a whole #, rewrite the whole number and write the fraction as 0 over the denominator of the fraction. 2. Denominators stay the same 3/8 - 1/4 = 3/8 – 2/8 = 1/8

FRACTIONS: MULTIPLICATION 1. Change mixed numbers to improper fractions a. Multiply the whole number by the denominator b. Add that to the numerator 2 3/4 x 5/8= 2.Cancel out 11/4 x 5/8= 55/32 = 1 23/32 3. Multiply the numerator times numerator and the denominator times the denominator 4. Simplify a. Rewrite improper fractions as mixed numbers b. Divide by common factors to simplify fraction s

FRACTIONS: DIVISION 1. Change improper fractions to mixed numbers 2. Rewrite first number 3.Change the division to multiplication 4.Flip the numbers of the second fractions 5. Cancel out if possible 6.Multiply numerators (top #s) 7. Multiply denominators (bottom 3s) 8. Simplify a. Rewrite improper fractions as mixed numbers b. Divide by common factors to simplify fraction s 1/4 divided by 3/5 1/4 x 5/3 = 5/12

DECIMALS : ADDITION 1. Line up decimals 2. Add 2.5 + 8.0 10.5

DECIMALS: SUBTRACTION 1. Line up decimals 2. Be careful with borrowing 3. Subtract 10. -0.98 9.02

DECIMALS: MULTIPLICATION 1. Don’t have to line up decimals 2. Multiply as if there is no decimals 3. Count the # of #’s behind the decimals in the problem & put that many #’s behind the decimal in the answer 5.1 -1 x.13 -2 153 +510.663

DECIMALS : DIVISION 1. Move decimal in divisor so that it is a whole # 2. Move the decimal in the dividend the same # of times 3. Divide.25 5.75 = 23

I GET IT!!!