Subtract 9/21 from 90/25, Solve 3 15/25

Subtract 9/21 from 90/25

1^st number: 3 15/25, 2^nd number: 9/21

90/25 - 9/21 is 111/35.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 21 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 25 × 21 = 525,
90/25 = 90 × 21/25 × 21 = 1890/525
Likewise, for the 2nd fraction, since 21 × 25 = 525,
9/21 = 9 × 25/21 × 25 = 225/525
Subtract the two like fractions:
1890/525 - 225/525 = 1890 - 225/525 = 1665/525
After reducing the fraction, the answer is 111/35
In mixed form: 36/35

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