Subtract 35/21 from 40/80, Solve 40/80

Subtract 35/21 from 40/80

1^st number: 40/80, 2^nd number: 1 14/21

40/80 - 35/21 is -7/6.

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,
40/80 = 40 × 21/80 × 21 = 840/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
35/21 = 35 × 80/21 × 80 = 2800/1680
Subtract the two like fractions:
840/1680 - 2800/1680 = 840 - 2800/1680 = -1960/1680
After reducing the fraction, the answer is -7/6

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