Subtract 35/15 from 7/21, Solve 7/21

Subtract 35/15 from 7/21

1^st number: 7/21, 2^nd number: 2 5/15

7/21 - 35/15 is -2/1.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
35/15 = 35 × 7/15 × 7 = 245/105
Subtract the two like fractions:
35/105 - 245/105 = 35 - 245/105 = -210/105
After reducing the fraction, the answer is -2/1

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