Add 15/20 and 72/90
15/20 + 72/90 is 31/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
15/20 = 15 × 9/20 × 9 = 135/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
72/90 = 72 × 2/90 × 2 = 144/180 - Add the two like fractions:
135/180 + 144/180 = 135 + 144/180 = 279/180 - 279/180 simplified gives 31/20
- So, 15/20 + 72/90 = 31/20
In mixed form: 111/20
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