Subtract 63/21 from 21/35, Solve 21/35

Subtract 63/21 from 21/35

1^st number: 21/35, 2^nd number: 3 0/21

21/35 - 63/21 is -12/5.

Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 35 × 3 = 105,
21/35 = 21 × 3/35 × 3 = 63/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
63/21 = 63 × 5/21 × 5 = 315/105
Subtract the two like fractions:
63/105 - 315/105 = 63 - 315/105 = -252/105
After reducing the fraction, the answer is -12/5

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