Subtract 81/28 from 42/40
1st number: 1 2/40, 2nd number: 2 25/28
42/40 - 81/28 is -129/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 28 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
42/40 = 42 × 7/40 × 7 = 294/280 - Likewise, for the 2nd fraction, since 28 × 10 = 280,
81/28 = 81 × 10/28 × 10 = 810/280 - Subtract the two like fractions:
294/280 - 810/280 = 294 - 810/280 = -516/280 - After reducing the fraction, the answer is -129/70
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