Subtract 45/21 from 27/80, Solve 27/80

Subtract 45/21 from 27/80

1^st number: 27/80, 2^nd number: 2 3/21

27/80 - 45/21 is -1011/560.

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,
27/80 = 27 × 21/80 × 21 = 567/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
45/21 = 45 × 80/21 × 80 = 3600/1680
Subtract the two like fractions:
567/1680 - 3600/1680 = 567 - 3600/1680 = -3033/1680
After reducing the fraction, the answer is -1011/560

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