Subtract 45/42 from 12/45, Solve 12/45

Subtract 45/42 from 12/45

1^st number: 12/45, 2^nd number: 1 3/42

12/45 - 45/42 is -169/210.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 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 42 × 15 = 630,
45/42 = 45 × 15/42 × 15 = 675/630
Subtract the two like fractions:
168/630 - 675/630 = 168 - 675/630 = -507/630
After reducing the fraction, the answer is -169/210

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