Subtract 1/40 from 60/42, Solve 1 18/42

Subtract 1/40 from 60/42

1^st number: 1 18/42, 2^nd number: 1/40

60/42 - 1/40 is 393/280.

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

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
60/42 = 60 × 20/42 × 20 = 1200/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
1/40 = 1 × 21/40 × 21 = 21/840
Subtract the two like fractions:
1200/840 - 21/840 = 1200 - 21/840 = 1179/840
After reducing the fraction, the answer is 393/280
In mixed form: 1113/280

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