Subtract 80/45 from 7/28, Solve 7/28

Subtract 80/45 from 7/28

1^st number: 7/28, 2^nd number: 1 35/45

7/28 - 80/45 is -55/36.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 45 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 28 × 45 = 1260,
7/28 = 7 × 45/28 × 45 = 315/1260
Likewise, for the 2nd fraction, since 45 × 28 = 1260,
80/45 = 80 × 28/45 × 28 = 2240/1260
Subtract the two like fractions:
315/1260 - 2240/1260 = 315 - 2240/1260 = -1925/1260
After reducing the fraction, the answer is -55/36

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