Subtract 25/7 from 40/45, Solve 40/45

Subtract 25/7 from 40/45

1^st number: 40/45, 2^nd number: 3 4/7

40/45 - 25/7 is -169/63.

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,
40/45 = 40 × 7/45 × 7 = 280/315
Likewise, for the 2nd fraction, since 7 × 45 = 315,
25/7 = 25 × 45/7 × 45 = 1125/315
Subtract the two like fractions:
280/315 - 1125/315 = 280 - 1125/315 = -845/315
After reducing the fraction, the answer is -169/63

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