Subtract 42/27 from 81/80
1st number: 1 1/80, 2nd number: 1 15/27
81/80 - 42/27 is -391/720.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 27 is 2160
Next, find the equivalent fraction of both fractional numbers with denominator 2160 - For the 1st fraction, since 80 × 27 = 2160,
81/80 = 81 × 27/80 × 27 = 2187/2160 - Likewise, for the 2nd fraction, since 27 × 80 = 2160,
42/27 = 42 × 80/27 × 80 = 3360/2160 - Subtract the two like fractions:
2187/2160 - 3360/2160 = 2187 - 3360/2160 = -1173/2160 - After reducing the fraction, the answer is -391/720
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