Subtract 9/8 from 72/84
1st number: 72/84, 2nd number: 1 1/8
72/84 - 9/8 is -15/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
72/84 = 72 × 2/84 × 2 = 144/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
9/8 = 9 × 21/8 × 21 = 189/168 - Subtract the two like fractions:
144/168 - 189/168 = 144 - 189/168 = -45/168 - After reducing the fraction, the answer is -15/56
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