Subtract 4/21 from 90/25, Solve 3 15/25

Subtract 4/21 from 90/25

1^st number: 3 15/25, 2^nd number: 4/21

90/25 - 4/21 is 358/105.

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,
4/21 = 4 × 25/21 × 25 = 100/525
Subtract the two like fractions:
1890/525 - 100/525 = 1890 - 100/525 = 1790/525
After reducing the fraction, the answer is 358/105
In mixed form: 343/105

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