Subtract 30/80 from 4/84, Solve 4/84

Subtract 30/80 from 4/84

4/84 - 30/80 is -55/168.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 84 × 20 = 1680,
4/84 = 4 × 20/84 × 20 = 80/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
30/80 = 30 × 21/80 × 21 = 630/1680
Subtract the two like fractions:
80/1680 - 630/1680 = 80 - 630/1680 = -550/1680
After reducing the fraction, the answer is -55/168

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