Subtract 45/5 from 18/84, Solve 18/84

Subtract 45/5 from 18/84

1^st number: 18/84, 2^nd number: 9 0/5

18/84 - 45/5 is -123/14.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Likewise, for the 2nd fraction, since 5 × 84 = 420,
45/5 = 45 × 84/5 × 84 = 3780/420
Subtract the two like fractions:
90/420 - 3780/420 = 90 - 3780/420 = -3690/420
After reducing the fraction, the answer is -123/14

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