Add 3/15 and 21/90
3/15 + 21/90 is 13/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
3/15 = 3 × 6/15 × 6 = 18/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Add the two like fractions:
18/90 + 21/90 = 18 + 21/90 = 39/90 - 39/90 simplified gives 13/30
- So, 3/15 + 21/90 = 13/30
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