Subtract 10/21 from 90/18, Solve 5 0/18

Subtract 10/21 from 90/18

1^st number: 5 0/18, 2^nd number: 10/21

90/18 - 10/21 is 95/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
90/18 = 90 × 7/18 × 7 = 630/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
10/21 = 10 × 6/21 × 6 = 60/126
Subtract the two like fractions:
630/126 - 60/126 = 630 - 60/126 = 570/126
After reducing the fraction, the answer is 95/21
In mixed form: 411/21

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