Subtract 72/21 from 36/5, Solve 7 1/5

Subtract 72/21 from 36/5

1^st number: 7 1/5, 2^nd number: 3 9/21

36/5 - 72/21 is 132/35.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
36/5 = 36 × 21/5 × 21 = 756/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
72/21 = 72 × 5/21 × 5 = 360/105
Subtract the two like fractions:
756/105 - 360/105 = 756 - 360/105 = 396/105
After reducing the fraction, the answer is 132/35
In mixed form: 327/35

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