Subtract 90/72 from 72/45, Solve 1 27/45

Subtract 90/72 from 72/45

1^st number: 1 27/45, 2^nd number: 1 18/72

72/45 - 90/72 is 7/20.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 72 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 45 × 8 = 360,
72/45 = 72 × 8/45 × 8 = 576/360
Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360
Subtract the two like fractions:
576/360 - 450/360 = 576 - 450/360 = 126/360
After reducing the fraction, the answer is 7/20

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