Subtract 30/28 from 7/15, Solve 7/15

Subtract 30/28 from 7/15

1^st number: 7/15, 2^nd number: 1 2/28

7/15 - 30/28 is -127/210.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
7/15 = 7 × 28/15 × 28 = 196/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
30/28 = 30 × 15/28 × 15 = 450/420
Subtract the two like fractions:
196/420 - 450/420 = 196 - 450/420 = -254/420
After reducing the fraction, the answer is -127/210

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