Subtract 35/21 from 30/80, Solve 30/80

Subtract 35/21 from 30/80

1^st number: 30/80, 2^nd number: 1 14/21

30/80 - 35/21 is -31/24.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
30/80 = 30 × 21/80 × 21 = 630/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
35/21 = 35 × 80/21 × 80 = 2800/1680
Subtract the two like fractions:
630/1680 - 2800/1680 = 630 - 2800/1680 = -2170/1680
After reducing the fraction, the answer is -31/24

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