Subtract 50/70 from 28/84, Solve 28/84

Subtract 50/70 from 28/84

28/84 - 50/70 is -8/21.

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,
28/84 = 28 × 5/84 × 5 = 140/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
50/70 = 50 × 6/70 × 6 = 300/420
Subtract the two like fractions:
140/420 - 300/420 = 140 - 300/420 = -160/420
After reducing the fraction, the answer is -8/21

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