Subtract 14/7 from 28/20, Solve 1 8/20

Subtract 14/7 from 28/20

1^st number: 1 8/20, 2^nd number: 2 0/7

28/20 - 14/7 is -3/5.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 20 × 7 = 140,
28/20 = 28 × 7/20 × 7 = 196/140
Likewise, for the 2nd fraction, since 7 × 20 = 140,
14/7 = 14 × 20/7 × 20 = 280/140
Subtract the two like fractions:
196/140 - 280/140 = 196 - 280/140 = -84/140
After reducing the fraction, the answer is -3/5

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