Subtract 90/25 from 9/8, Solve 1 1/8

Subtract 90/25 from 9/8

1^st number: 1 1/8, 2^nd number: 3 15/25

9/8 - 90/25 is -99/40.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 25 is 200

Next, find the equivalent fraction of both fractional numbers with denominator 200
For the 1st fraction, since 8 × 25 = 200,
9/8 = 9 × 25/8 × 25 = 225/200
Likewise, for the 2nd fraction, since 25 × 8 = 200,
90/25 = 90 × 8/25 × 8 = 720/200
Subtract the two like fractions:
225/200 - 720/200 = 225 - 720/200 = -495/200
After reducing the fraction, the answer is -99/40

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