Subtract 84/72 from 15/42
1st number: 15/42, 2nd number: 1 12/72
15/42 - 84/72 is -17/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
15/42 = 15 × 12/42 × 12 = 180/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
84/72 = 84 × 7/72 × 7 = 588/504 - Subtract the two like fractions:
180/504 - 588/504 = 180 - 588/504 = -408/504 - After reducing the fraction, the answer is -17/21
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