Subtract 21/7 from 10/15, Solve 10/15

Subtract 21/7 from 10/15

1^st number: 10/15, 2^nd number: 3 0/7

10/15 - 21/7 is -7/3.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
10/15 = 10 × 7/15 × 7 = 70/105
Likewise, for the 2nd fraction, since 7 × 15 = 105,
21/7 = 21 × 15/7 × 15 = 315/105
Subtract the two like fractions:
70/105 - 315/105 = 70 - 315/105 = -245/105
After reducing the fraction, the answer is -7/3

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