Subtract 7/75 from 70/21, Solve 3 7/21

Subtract 7/75 from 70/21

1^st number: 3 7/21, 2^nd number: 7/75

70/21 - 7/75 is 81/25.

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,
70/21 = 70 × 25/21 × 25 = 1750/525
Likewise, for the 2nd fraction, since 75 × 7 = 525,
7/75 = 7 × 7/75 × 7 = 49/525
Subtract the two like fractions:
1750/525 - 49/525 = 1750 - 49/525 = 1701/525
After reducing the fraction, the answer is 81/25
In mixed form: 36/25

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