Subtract 25/18 from 18/20, Solve 18/20

Subtract 25/18 from 18/20

1^st number: 18/20, 2^nd number: 1 7/18

18/20 - 25/18 is -22/45.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 20 × 9 = 180,
18/20 = 18 × 9/20 × 9 = 162/180
Likewise, for the 2nd fraction, since 18 × 10 = 180,
25/18 = 25 × 10/18 × 10 = 250/180
Subtract the two like fractions:
162/180 - 250/180 = 162 - 250/180 = -88/180
After reducing the fraction, the answer is -22/45

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