Subtract 42/16 from 21/28
1st number: 21/28, 2nd number: 2 10/16
21/28 - 42/16 is -15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 16 is 112
Next, find the equivalent fraction of both fractional numbers with denominator 112 - For the 1st fraction, since 28 × 4 = 112,
21/28 = 21 × 4/28 × 4 = 84/112 - Likewise, for the 2nd fraction, since 16 × 7 = 112,
42/16 = 42 × 7/16 × 7 = 294/112 - Subtract the two like fractions:
84/112 - 294/112 = 84 - 294/112 = -210/112 - After reducing the fraction, the answer is -15/8
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