Subtract 9/8 from 21/7
1st number: 3 0/7, 2nd number: 1 1/8
21/7 - 9/8 is 15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
21/7 = 21 × 8/7 × 8 = 168/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
9/8 = 9 × 7/8 × 7 = 63/56 - Subtract the two like fractions:
168/56 - 63/56 = 168 - 63/56 = 105/56 - After reducing the fraction, the answer is 15/8
- In mixed form: 17/8
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