Subtract 42/24 from 6/21, Solve 6/21

Subtract 42/24 from 6/21

1^st number: 6/21, 2^nd number: 1 18/24

6/21 - 42/24 is -41/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
6/21 = 6 × 8/21 × 8 = 48/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
42/24 = 42 × 7/24 × 7 = 294/168
Subtract the two like fractions:
48/168 - 294/168 = 48 - 294/168 = -246/168
After reducing the fraction, the answer is -41/28

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