Subtract 21/16 from 30/72
1st number: 30/72, 2nd number: 1 5/16
30/72 - 21/16 is -43/48.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 16 is 144
Next, find the equivalent fraction of both fractional numbers with denominator 144 - For the 1st fraction, since 72 × 2 = 144,
30/72 = 30 × 2/72 × 2 = 60/144 - Likewise, for the 2nd fraction, since 16 × 9 = 144,
21/16 = 21 × 9/16 × 9 = 189/144 - Subtract the two like fractions:
60/144 - 189/144 = 60 - 189/144 = -129/144 - After reducing the fraction, the answer is -43/48
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