Subtract 15/42 from 16/21
16/21 - 15/42 is 17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
16/21 = 16 × 2/21 × 2 = 32/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
15/42 = 15 × 1/42 × 1 = 15/42 - Subtract the two like fractions:
32/42 - 15/42 = 32 - 15/42 = 17/42
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