Subtract 42/9 from 72/84
1st number: 72/84, 2nd number: 4 6/9
72/84 - 42/9 is -80/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
72/84 = 72 × 3/84 × 3 = 216/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
42/9 = 42 × 28/9 × 28 = 1176/252 - Subtract the two like fractions:
216/252 - 1176/252 = 216 - 1176/252 = -960/252 - After reducing the fraction, the answer is -80/21
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