Add 15/20 and 21/90
15/20 + 21/90 is 59/60.
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,
21/90 = 21 × 2/90 × 2 = 42/180 - Add the two like fractions:
135/180 + 42/180 = 135 + 42/180 = 177/180 - 177/180 simplified gives 59/60
- So, 15/20 + 21/90 = 59/60
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