Subtract 9/30 from 72/20, Solve 3 12/20

Subtract 9/30 from 72/20

1^st number: 3 12/20, 2^nd number: 9/30

72/20 - 9/30 is 33/10.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 30 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 20 × 3 = 60,
72/20 = 72 × 3/20 × 3 = 216/60
Likewise, for the 2nd fraction, since 30 × 2 = 60,
9/30 = 9 × 2/30 × 2 = 18/60
Subtract the two like fractions:
216/60 - 18/60 = 216 - 18/60 = 198/60
After reducing the fraction, the answer is 33/10
In mixed form: 33/10

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