Subtract 21/7 from 6/8
1st number: 6/8, 2nd number: 3 0/7
6/8 - 21/7 is -9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 7 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 8 × 7 = 56,
6/8 = 6 × 7/8 × 7 = 42/56 - Likewise, for the 2nd fraction, since 7 × 8 = 56,
21/7 = 21 × 8/7 × 8 = 168/56 - Subtract the two like fractions:
42/56 - 168/56 = 42 - 168/56 = -126/56 - After reducing the fraction, the answer is -9/4
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