Subtract 21/16 from 20/72
1st number: 20/72, 2nd number: 1 5/16
20/72 - 21/16 is -149/144.
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,
20/72 = 20 × 2/72 × 2 = 40/144 - Likewise, for the 2nd fraction, since 16 × 9 = 144,
21/16 = 21 × 9/16 × 9 = 189/144 - Subtract the two like fractions:
40/144 - 189/144 = 40 - 189/144 = -149/144
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