Subtract 4/40 from 45/42, Solve 1 3/42

Subtract 4/40 from 45/42

1^st number: 1 3/42, 2^nd number: 4/40

45/42 - 4/40 is 34/35.

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,
45/42 = 45 × 20/42 × 20 = 900/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
4/40 = 4 × 21/40 × 21 = 84/840
Subtract the two like fractions:
900/840 - 84/840 = 900 - 84/840 = 816/840
After reducing the fraction, the answer is 34/35

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