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

Subtract 45/5 from 18/72

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

18/72 - 45/5 is -35/4.

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,
18/72 = 18 × 5/72 × 5 = 90/360
Likewise, for the 2nd fraction, since 5 × 72 = 360,
45/5 = 45 × 72/5 × 72 = 3240/360
Subtract the two like fractions:
90/360 - 3240/360 = 90 - 3240/360 = -3150/360
After reducing the fraction, the answer is -35/4

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