Subtract 21/8 from 42/49
1st number: 42/49, 2nd number: 2 5/8
42/49 - 21/8 is -99/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 8 is 392
Next, find the equivalent fraction of both fractional numbers with denominator 392 - For the 1st fraction, since 49 × 8 = 392,
42/49 = 42 × 8/49 × 8 = 336/392 - Likewise, for the 2nd fraction, since 8 × 49 = 392,
21/8 = 21 × 49/8 × 49 = 1029/392 - Subtract the two like fractions:
336/392 - 1029/392 = 336 - 1029/392 = -693/392 - After reducing the fraction, the answer is -99/56
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