Subtract 90/48 from 4/21, Solve 4/21

Subtract 90/48 from 4/21

1^st number: 4/21, 2^nd number: 1 42/48

4/21 - 90/48 is -283/168.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 48 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 21 × 16 = 336,
4/21 = 4 × 16/21 × 16 = 64/336
Likewise, for the 2nd fraction, since 48 × 7 = 336,
90/48 = 90 × 7/48 × 7 = 630/336
Subtract the two like fractions:
64/336 - 630/336 = 64 - 630/336 = -566/336
After reducing the fraction, the answer is -283/168

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