Subtract 70/21 from 30/25, Solve 1 5/25

Subtract 70/21 from 30/25

1^st number: 1 5/25, 2^nd number: 3 7/21

30/25 - 70/21 is -32/15.

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,
30/25 = 30 × 21/25 × 21 = 630/525
Likewise, for the 2nd fraction, since 21 × 25 = 525,
70/21 = 70 × 25/21 × 25 = 1750/525
Subtract the two like fractions:
630/525 - 1750/525 = 630 - 1750/525 = -1120/525
After reducing the fraction, the answer is -32/15

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