Subtract 4/72 from 21/5, Solve 4 1/5

Subtract 4/72 from 21/5

1^st number: 4 1/5, 2^nd number: 4/72

21/5 - 4/72 is 373/90.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 72 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 5 × 72 = 360,
21/5 = 21 × 72/5 × 72 = 1512/360
Likewise, for the 2nd fraction, since 72 × 5 = 360,
4/72 = 4 × 5/72 × 5 = 20/360
Subtract the two like fractions:
1512/360 - 20/360 = 1512 - 20/360 = 1492/360
After reducing the fraction, the answer is 373/90
In mixed form: 413/90

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