Subtract 42/10 from 7/28, Solve 7/28

Subtract 42/10 from 7/28

1^st number: 7/28, 2^nd number: 4 2/10

7/28 - 42/10 is -79/20.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 10 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 28 × 5 = 140,
7/28 = 7 × 5/28 × 5 = 35/140
Likewise, for the 2nd fraction, since 10 × 14 = 140,
42/10 = 42 × 14/10 × 14 = 588/140
Subtract the two like fractions:
35/140 - 588/140 = 35 - 588/140 = -553/140
After reducing the fraction, the answer is -79/20

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