Subtract 25/10 from 90/21, Solve 4 6/21

Subtract 25/10 from 90/21

1^st number: 4 6/21, 2^nd number: 2 5/10

90/21 - 25/10 is 25/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
90/21 = 90 × 10/21 × 10 = 900/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
25/10 = 25 × 21/10 × 21 = 525/210
Subtract the two like fractions:
900/210 - 525/210 = 900 - 525/210 = 375/210
After reducing the fraction, the answer is 25/14
In mixed form: 111/14

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