Subtract 30/28 from 15/20, Solve 15/20

Subtract 30/28 from 15/20

1^st number: 15/20, 2^nd number: 1 2/28

15/20 - 30/28 is -9/28.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 20 × 7 = 140,
15/20 = 15 × 7/20 × 7 = 105/140
Likewise, for the 2nd fraction, since 28 × 5 = 140,
30/28 = 30 × 5/28 × 5 = 150/140
Subtract the two like fractions:
105/140 - 150/140 = 105 - 150/140 = -45/140
After reducing the fraction, the answer is -9/28

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