Subtract 80/7 from 70/45, Solve 1 25/45

Subtract 80/7 from 70/45

1^st number: 1 25/45, 2^nd number: 11 3/7

70/45 - 80/7 is -622/63.

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,
70/45 = 70 × 7/45 × 7 = 490/315
Likewise, for the 2nd fraction, since 7 × 45 = 315,
80/7 = 80 × 45/7 × 45 = 3600/315
Subtract the two like fractions:
490/315 - 3600/315 = 490 - 3600/315 = -3110/315
After reducing the fraction, the answer is -622/63

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