Subtract 15/4 from 72/42
1st number: 1 30/42, 2nd number: 3 3/4
72/42 - 15/4 is -57/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
72/42 = 72 × 2/42 × 2 = 144/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
15/4 = 15 × 21/4 × 21 = 315/84 - Subtract the two like fractions:
144/84 - 315/84 = 144 - 315/84 = -171/84 - After reducing the fraction, the answer is -57/28
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