Subtract 9/21 from 90/5, Solve 18 0/5

Subtract 9/21 from 90/5

1^st number: 18 0/5, 2^nd number: 9/21

90/5 - 9/21 is 123/7.

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,
9/21 = 9 × 5/21 × 5 = 45/105
Subtract the two like fractions:
1890/105 - 45/105 = 1890 - 45/105 = 1845/105
After reducing the fraction, the answer is 123/7
In mixed form: 174/7

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