Subtract 3/21 from 40/25, Solve 1 15/25

Subtract 3/21 from 40/25

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

40/25 - 3/21 is 51/35.

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,
40/25 = 40 × 21/25 × 21 = 840/525
Likewise, for the 2nd fraction, since 21 × 25 = 525,
3/21 = 3 × 25/21 × 25 = 75/525
Subtract the two like fractions:
840/525 - 75/525 = 840 - 75/525 = 765/525
After reducing the fraction, the answer is 51/35
In mixed form: 116/35

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