Subtract 21/84 from 90/18, Solve 5 0/18

Subtract 21/84 from 90/18

1^st number: 5 0/18, 2^nd number: 21/84

90/18 - 21/84 is 19/4.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 84 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 18 × 14 = 252,
90/18 = 90 × 14/18 × 14 = 1260/252
Likewise, for the 2nd fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252
Subtract the two like fractions:
1260/252 - 63/252 = 1260 - 63/252 = 1197/252
After reducing the fraction, the answer is 19/4
In mixed form: 43/4

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