Subtract 18/80 from 90/2, Solve 45 0/2

Subtract 18/80 from 90/2

1^st number: 45 0/2, 2^nd number: 18/80

90/2 - 18/80 is 1791/40.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 2 × 40 = 80,
90/2 = 90 × 40/2 × 40 = 3600/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
18/80 = 18 × 1/80 × 1 = 18/80
Subtract the two like fractions:
3600/80 - 18/80 = 3600 - 18/80 = 3582/80
After reducing the fraction, the answer is 1791/40
In mixed form: 4431/40

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