Subtract 12/20 from 16/21, Solve 16/21

Subtract 12/20 from 16/21

16/21 - 12/20 is 17/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
16/21 = 16 × 20/21 × 20 = 320/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420
Subtract the two like fractions:
320/420 - 252/420 = 320 - 252/420 = 68/420
After reducing the fraction, the answer is 17/105

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