Subtract 4/20 from 42/27, Solve 1 15/27

Subtract 4/20 from 42/27

1^st number: 1 15/27, 2^nd number: 4/20

42/27 - 4/20 is 61/45.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 20 is 540

Next, find the equivalent fraction of both fractional numbers with denominator 540
For the 1st fraction, since 27 × 20 = 540,
42/27 = 42 × 20/27 × 20 = 840/540
Likewise, for the 2nd fraction, since 20 × 27 = 540,
4/20 = 4 × 27/20 × 27 = 108/540
Subtract the two like fractions:
840/540 - 108/540 = 840 - 108/540 = 732/540
After reducing the fraction, the answer is 61/45
In mixed form: 116/45

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