Subtract 27/21 from 90/5, Solve 18 0/5

Subtract 27/21 from 90/5

1^st number: 18 0/5, 2^nd number: 1 6/21

90/5 - 27/21 is 117/7.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
90/5 = 90 × 21/5 × 21 = 1890/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
27/21 = 27 × 5/21 × 5 = 135/105
Subtract the two like fractions:
1890/105 - 135/105 = 1890 - 135/105 = 1755/105
After reducing the fraction, the answer is 117/7
In mixed form: 165/7

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