Subtract 21/10 from 90/25, Solve 3 15/25

Subtract 21/10 from 90/25

1^st number: 3 15/25, 2^nd number: 2 1/10

90/25 - 21/10 is 3/2.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 10 is 50

Next, find the equivalent fraction of both fractional numbers with denominator 50
For the 1st fraction, since 25 × 2 = 50,
90/25 = 90 × 2/25 × 2 = 180/50
Likewise, for the 2nd fraction, since 10 × 5 = 50,
21/10 = 21 × 5/10 × 5 = 105/50
Subtract the two like fractions:
180/50 - 105/50 = 180 - 105/50 = 75/50
After reducing the fraction, the answer is 3/2
In mixed form: 11/2

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