Subtract 9/49 from 72/20, Solve 3 12/20

Subtract 9/49 from 72/20

1^st number: 3 12/20, 2^nd number: 9/49

72/20 - 9/49 is 837/245.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 49 is 980

Next, find the equivalent fraction of both fractional numbers with denominator 980
For the 1st fraction, since 20 × 49 = 980,
72/20 = 72 × 49/20 × 49 = 3528/980
Likewise, for the 2nd fraction, since 49 × 20 = 980,
9/49 = 9 × 20/49 × 20 = 180/980
Subtract the two like fractions:
3528/980 - 180/980 = 3528 - 180/980 = 3348/980
After reducing the fraction, the answer is 837/245
In mixed form: 3102/245

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