Subtract 7/15 from 21/30
21/30 - 7/15 is 7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 15 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Likewise, for the 2nd fraction, since 15 × 2 = 30,
7/15 = 7 × 2/15 × 2 = 14/30 - Subtract the two like fractions:
21/30 - 14/30 = 21 - 14/30 = 7/30
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