Subtract 81/72 from 25/42
1st number: 25/42, 2nd number: 1 9/72
25/42 - 81/72 is -89/168.
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,
25/42 = 25 × 12/42 × 12 = 300/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Subtract the two like fractions:
300/504 - 567/504 = 300 - 567/504 = -267/504 - After reducing the fraction, the answer is -89/168
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