Subtract 45/42 from 4/20, Solve 4/20

Subtract 45/42 from 4/20

1^st number: 4/20, 2^nd number: 1 3/42

4/20 - 45/42 is -61/70.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
4/20 = 4 × 21/20 × 21 = 84/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
45/42 = 45 × 10/42 × 10 = 450/420
Subtract the two like fractions:
84/420 - 450/420 = 84 - 450/420 = -366/420
After reducing the fraction, the answer is -61/70

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