Subtract 7/54 from 81/40, Solve 2 1/40

Subtract 7/54 from 81/40

1^st number: 2 1/40, 2^nd number: 7/54

81/40 - 7/54 is 2047/1080.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 54 is 1080

Next, find the equivalent fraction of both fractional numbers with denominator 1080
For the 1st fraction, since 40 × 27 = 1080,
81/40 = 81 × 27/40 × 27 = 2187/1080
Likewise, for the 2nd fraction, since 54 × 20 = 1080,
7/54 = 7 × 20/54 × 20 = 140/1080
Subtract the two like fractions:
2187/1080 - 140/1080 = 2187 - 140/1080 = 2047/1080
In mixed form: 1967/1080

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