Subtract 12/27 from 90/20, Solve 4 10/20

Subtract 12/27 from 90/20

1^st number: 4 10/20, 2^nd number: 12/27

90/20 - 12/27 is 73/18.

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

Next, find the equivalent fraction of both fractional numbers with denominator 540
For the 1st fraction, since 20 × 27 = 540,
90/20 = 90 × 27/20 × 27 = 2430/540
Likewise, for the 2nd fraction, since 27 × 20 = 540,
12/27 = 12 × 20/27 × 20 = 240/540
Subtract the two like fractions:
2430/540 - 240/540 = 2430 - 240/540 = 2190/540
After reducing the fraction, the answer is 73/18
In mixed form: 41/18

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