Subtract 63/42 from 45/40, Solve 1 5/40

Subtract 63/42 from 45/40

1^st number: 1 5/40, 2^nd number: 1 21/42

45/40 - 63/42 is -3/8.

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,
45/40 = 45 × 21/40 × 21 = 945/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
63/42 = 63 × 20/42 × 20 = 1260/840
Subtract the two like fractions:
945/840 - 1260/840 = 945 - 1260/840 = -315/840
After reducing the fraction, the answer is -3/8

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