Subtract 64/18 from 4/21, Solve 4/21

Subtract 64/18 from 4/21

1^st number: 4/21, 2^nd number: 3 10/18

4/21 - 64/18 is -212/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
4/21 = 4 × 6/21 × 6 = 24/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
64/18 = 64 × 7/18 × 7 = 448/126
Subtract the two like fractions:
24/126 - 448/126 = 24 - 448/126 = -424/126
After reducing the fraction, the answer is -212/63

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