Subtract 48/42 from 21/48, Solve 21/48

Subtract 48/42 from 21/48

1^st number: 21/48, 2^nd number: 1 6/42

21/48 - 48/42 is -79/112.

Find the least common denominator or LCM of the two denominators:
LCM of 48 and 42 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 48 × 7 = 336,
21/48 = 21 × 7/48 × 7 = 147/336
Likewise, for the 2nd fraction, since 42 × 8 = 336,
48/42 = 48 × 8/42 × 8 = 384/336
Subtract the two like fractions:
147/336 - 384/336 = 147 - 384/336 = -237/336
After reducing the fraction, the answer is -79/112

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