Subtract 21/9 from 36/80, Solve 36/80

Subtract 21/9 from 36/80

1^st number: 36/80, 2^nd number: 2 3/9

36/80 - 21/9 is -113/60.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
36/80 = 36 × 9/80 × 9 = 324/720
Likewise, for the 2nd fraction, since 9 × 80 = 720,
21/9 = 21 × 80/9 × 80 = 1680/720
Subtract the two like fractions:
324/720 - 1680/720 = 324 - 1680/720 = -1356/720
After reducing the fraction, the answer is -113/60

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