Math formulas

Reducing fractions to lowest common denominator

Find multiples of each denominator, finding the smallest common denominator for each fraction. Multiply denominator with by number that formed common denominator eg. 2/9 3/7 smallest common denominator is 63. what do I need t multiply to get 63 from 9. 9X7 =63 multiply number by 7: 2X7 = 14 new fraction is 14/63: Next what do I need to multiply 7 to get 63: Multiply 7 X 9 = 63; multiply number by same number 3X9 = 27 27/63 new fraction.

Subtracting

find lowest common denomator and subtract 5/12 - 2/12 = 3/12

Adding fractions

find lowest common denominator and add 14/63 + 27/63 = 41/63

Multiplying fractions

4/7 X 5/8 = 20/56 = 20div 2= 10 10 div 2 =5 56div 2 - 28 28 div 2 = 14 answer 5/14

Dividing franctins = kiss and flip

5/7 div 2/3 5/7 div 3/2 and then multiply 5/7 X 3/2 = 15/14 = 1 1/14