Subtract 54/80 from 15/21, Solve 15/21

Subtract 54/80 from 15/21

15/21 - 54/80 is 11/280.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
15/21 = 15 × 80/21 × 80 = 1200/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
54/80 = 54 × 21/80 × 21 = 1134/1680
Subtract the two like fractions:
1200/1680 - 1134/1680 = 1200 - 1134/1680 = 66/1680
After reducing the fraction, the answer is 11/280

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