Subtract 35/21 from 27/20, Solve 1 7/20

Subtract 35/21 from 27/20

1^st number: 1 7/20, 2^nd number: 1 14/21

27/20 - 35/21 is -19/60.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
27/20 = 27 × 21/20 × 21 = 567/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
35/21 = 35 × 20/21 × 20 = 700/420
Subtract the two like fractions:
567/420 - 700/420 = 567 - 700/420 = -133/420
After reducing the fraction, the answer is -19/60

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