Subtract 70/42 from 12/25, Solve 12/25

Subtract 70/42 from 12/25

1^st number: 12/25, 2^nd number: 1 28/42

12/25 - 70/42 is -89/75.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 42 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 25 × 42 = 1050,
12/25 = 12 × 42/25 × 42 = 504/1050
Likewise, for the 2nd fraction, since 42 × 25 = 1050,
70/42 = 70 × 25/42 × 25 = 1750/1050
Subtract the two like fractions:
504/1050 - 1750/1050 = 504 - 1750/1050 = -1246/1050
After reducing the fraction, the answer is -89/75

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