Subtract 50/70 from 20/84, Solve 20/84

Subtract 50/70 from 20/84

20/84 - 50/70 is -10/21.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
20/84 = 20 × 5/84 × 5 = 100/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
50/70 = 50 × 6/70 × 6 = 300/420
Subtract the two like fractions:
100/420 - 300/420 = 100 - 300/420 = -200/420
After reducing the fraction, the answer is -10/21

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