Subtract 7/9 from 15/20, Solve 15/20

Subtract 7/9 from 15/20

15/20 - 7/9 is -1/36.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 20 × 9 = 180,
15/20 = 15 × 9/20 × 9 = 135/180
Likewise, for the 2nd fraction, since 9 × 20 = 180,
7/9 = 7 × 20/9 × 20 = 140/180
Subtract the two like fractions:
135/180 - 140/180 = 135 - 140/180 = -5/180
After reducing the fraction, the answer is -1/36

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