Subtract 9/15 from 21/28
21/28 - 9/15 is 3/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
9/15 = 9 × 28/15 × 28 = 252/420 - Subtract the two like fractions:
315/420 - 252/420 = 315 - 252/420 = 63/420 - After reducing the fraction, the answer is 3/20
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