Subtract 9/7 from 45/80, Solve 45/80

Subtract 9/7 from 45/80

1^st number: 45/80, 2^nd number: 1 2/7

45/80 - 9/7 is -81/112.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
45/80 = 45 × 7/80 × 7 = 315/560
Likewise, for the 2nd fraction, since 7 × 80 = 560,
9/7 = 9 × 80/7 × 80 = 720/560
Subtract the two like fractions:
315/560 - 720/560 = 315 - 720/560 = -405/560
After reducing the fraction, the answer is -81/112

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