Subtract 45/5 from 90/72, Solve 1 18/72

Subtract 45/5 from 90/72

1^st number: 1 18/72, 2^nd number: 9 0/5

90/72 - 45/5 is -31/4.

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

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360
Likewise, for the 2nd fraction, since 5 × 72 = 360,
45/5 = 45 × 72/5 × 72 = 3240/360
Subtract the two like fractions:
450/360 - 3240/360 = 450 - 3240/360 = -2790/360
After reducing the fraction, the answer is -31/4

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