Subtract 42/9 from 90/5, Solve 18 0/5

Subtract 42/9 from 90/5

1^st number: 18 0/5, 2^nd number: 4 6/9

90/5 - 42/9 is 40/3.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 9 is 45

Next, find the equivalent fraction of both fractional numbers with denominator 45
For the 1st fraction, since 5 × 9 = 45,
90/5 = 90 × 9/5 × 9 = 810/45
Likewise, for the 2nd fraction, since 9 × 5 = 45,
42/9 = 42 × 5/9 × 5 = 210/45
Subtract the two like fractions:
810/45 - 210/45 = 810 - 210/45 = 600/45
After reducing the fraction, the answer is 40/3
In mixed form: 131/3

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