Subtract 80/45 from 27/21, Solve 1 6/21

Subtract 80/45 from 27/21

1^st number: 1 6/21, 2^nd number: 1 35/45

27/21 - 80/45 is -31/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
27/21 = 27 × 15/21 × 15 = 405/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
80/45 = 80 × 7/45 × 7 = 560/315
Subtract the two like fractions:
405/315 - 560/315 = 405 - 560/315 = -155/315
After reducing the fraction, the answer is -31/63

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