Subtract 9/20 from 3/84, Solve 3/84

Subtract 9/20 from 3/84

3/84 - 9/20 is -29/70.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
3/84 = 3 × 5/84 × 5 = 15/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420
Subtract the two like fractions:
15/420 - 189/420 = 15 - 189/420 = -174/420
After reducing the fraction, the answer is -29/70

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