Subtract 63/27 from 1/21, Solve 1/21

Subtract 63/27 from 1/21

1^st number: 1/21, 2^nd number: 2 9/27

1/21 - 63/27 is -16/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
1/21 = 1 × 9/21 × 9 = 9/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
63/27 = 63 × 7/27 × 7 = 441/189
Subtract the two like fractions:
9/189 - 441/189 = 9 - 441/189 = -432/189
After reducing the fraction, the answer is -16/7

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