Subtract 16/18 from 21/75, Solve 21/75

Subtract 16/18 from 21/75

21/75 - 16/18 is -137/225.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 18 is 450

Next, find the equivalent fraction of both fractional numbers with denominator 450
For the 1st fraction, since 75 × 6 = 450,
21/75 = 21 × 6/75 × 6 = 126/450
Likewise, for the 2nd fraction, since 18 × 25 = 450,
16/18 = 16 × 25/18 × 25 = 400/450
Subtract the two like fractions:
126/450 - 400/450 = 126 - 400/450 = -274/450
After reducing the fraction, the answer is -137/225

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