Subtract 4/5 from 30/72, Solve 30/72

Subtract 4/5 from 30/72

30/72 - 4/5 is -23/60.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 5 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 72 × 5 = 360,
30/72 = 30 × 5/72 × 5 = 150/360
Likewise, for the 2nd fraction, since 5 × 72 = 360,
4/5 = 4 × 72/5 × 72 = 288/360
Subtract the two like fractions:
150/360 - 288/360 = 150 - 288/360 = -138/360
After reducing the fraction, the answer is -23/60

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