Subtract 9/7 from 12/45, Solve 12/45

Subtract 9/7 from 12/45

1^st number: 12/45, 2^nd number: 1 2/7

12/45 - 9/7 is -107/105.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 7 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315
Likewise, for the 2nd fraction, since 7 × 45 = 315,
9/7 = 9 × 45/7 × 45 = 405/315
Subtract the two like fractions:
84/315 - 405/315 = 84 - 405/315 = -321/315
After reducing the fraction, the answer is -107/105

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