Subtract 21/20 from 90/42, Solve 2 6/42

Subtract 21/20 from 90/42

1^st number: 2 6/42, 2^nd number: 1 1/20

90/42 - 21/20 is 153/140.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
90/42 = 90 × 10/42 × 10 = 900/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420
Subtract the two like fractions:
900/420 - 441/420 = 900 - 441/420 = 459/420
After reducing the fraction, the answer is 153/140
In mixed form: 113/140

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