Subtract 4/80 from 28/72, Solve 28/72

Subtract 4/80 from 28/72

28/72 - 4/80 is 61/180.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 80 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 72 × 10 = 720,
28/72 = 28 × 10/72 × 10 = 280/720
Likewise, for the 2nd fraction, since 80 × 9 = 720,
4/80 = 4 × 9/80 × 9 = 36/720
Subtract the two like fractions:
280/720 - 36/720 = 280 - 36/720 = 244/720
After reducing the fraction, the answer is 61/180

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