Subtract 18/16 from 21/7
1st number: 3 0/7, 2nd number: 1 2/16
21/7 - 18/16 is 15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 16 is 112
Next, find the equivalent fraction of both fractional numbers with denominator 112 - For the 1st fraction, since 7 × 16 = 112,
21/7 = 21 × 16/7 × 16 = 336/112 - Likewise, for the 2nd fraction, since 16 × 7 = 112,
18/16 = 18 × 7/16 × 7 = 126/112 - Subtract the two like fractions:
336/112 - 126/112 = 336 - 126/112 = 210/112 - After reducing the fraction, the answer is 15/8
- In mixed form: 17/8
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