Subtract 48/42 from 81/40, Solve 2 1/40

Subtract 48/42 from 81/40

1^st number: 2 1/40, 2^nd number: 1 6/42

81/40 - 48/42 is 247/280.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
48/42 = 48 × 20/42 × 20 = 960/840
Subtract the two like fractions:
1701/840 - 960/840 = 1701 - 960/840 = 741/840
After reducing the fraction, the answer is 247/280

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