Subtract 20/25 from 49/21, Solve 2 7/21

Subtract 20/25 from 49/21

1^st number: 2 7/21, 2^nd number: 20/25

49/21 - 20/25 is 23/15.

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

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 21 × 25 = 525,
49/21 = 49 × 25/21 × 25 = 1225/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
20/25 = 20 × 21/25 × 21 = 420/525
Subtract the two like fractions:
1225/525 - 420/525 = 1225 - 420/525 = 805/525
After reducing the fraction, the answer is 23/15
In mixed form: 18/15

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