Add 21/90 and 15/30
21/90 + 15/30 is 11/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
15/30 = 15 × 3/30 × 3 = 45/90 - Add the two like fractions:
21/90 + 45/90 = 21 + 45/90 = 66/90 - 66/90 simplified gives 11/15
- So, 21/90 + 15/30 = 11/15
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