Subtract 54/48 from 21/70, Solve 21/70

Subtract 54/48 from 21/70

1^st number: 21/70, 2^nd number: 1 6/48

21/70 - 54/48 is -33/40.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 48 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 70 × 24 = 1680,
21/70 = 21 × 24/70 × 24 = 504/1680
Likewise, for the 2nd fraction, since 48 × 35 = 1680,
54/48 = 54 × 35/48 × 35 = 1890/1680
Subtract the two like fractions:
504/1680 - 1890/1680 = 504 - 1890/1680 = -1386/1680
After reducing the fraction, the answer is -33/40

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