Subtract 21/25 from 30/36, Solve 30/36

Subtract 21/25 from 30/36

30/36 - 21/25 is -1/150.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 25 is 900

Next, find the equivalent fraction of both fractional numbers with denominator 900
For the 1st fraction, since 36 × 25 = 900,
30/36 = 30 × 25/36 × 25 = 750/900
Likewise, for the 2nd fraction, since 25 × 36 = 900,
21/25 = 21 × 36/25 × 36 = 756/900
Subtract the two like fractions:
750/900 - 756/900 = 750 - 756/900 = -6/900
After reducing the fraction, the answer is -1/150

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