Subtract 21/63 from 7/80, Solve 7/80

Subtract 21/63 from 7/80

7/80 - 21/63 is -59/240.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040

Next, find the equivalent fraction of both fractional numbers with denominator 5040
For the 1st fraction, since 80 × 63 = 5040,
7/80 = 7 × 63/80 × 63 = 441/5040
Likewise, for the 2nd fraction, since 63 × 80 = 5040,
21/63 = 21 × 80/63 × 80 = 1680/5040
Subtract the two like fractions:
441/5040 - 1680/5040 = 441 - 1680/5040 = -1239/5040
After reducing the fraction, the answer is -59/240

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