Subtract 10/75 from 15/21, Solve 15/21

Subtract 10/75 from 15/21

15/21 - 10/75 is 61/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 75 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 21 × 25 = 525,
15/21 = 15 × 25/21 × 25 = 375/525
Likewise, for the 2nd fraction, since 75 × 7 = 525,
10/75 = 10 × 7/75 × 7 = 70/525
Subtract the two like fractions:
375/525 - 70/525 = 375 - 70/525 = 305/525
After reducing the fraction, the answer is 61/105

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