Subtract 49/70 from 12/45, Solve 12/45

Subtract 49/70 from 12/45

12/45 - 49/70 is -13/30.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
12/45 = 12 × 14/45 × 14 = 168/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
49/70 = 49 × 9/70 × 9 = 441/630
Subtract the two like fractions:
168/630 - 441/630 = 168 - 441/630 = -273/630
After reducing the fraction, the answer is -13/30

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