Subtract 70/63 from 45/80, Solve 45/80

Subtract 70/63 from 45/80

1^st number: 45/80, 2^nd number: 1 7/63

45/80 - 70/63 is -79/144.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040

Next, find the equivalent fraction of both fractional numbers with denominator 5040
For the 1st fraction, since 80 × 63 = 5040,
45/80 = 45 × 63/80 × 63 = 2835/5040
Likewise, for the 2nd fraction, since 63 × 80 = 5040,
70/63 = 70 × 80/63 × 80 = 5600/5040
Subtract the two like fractions:
2835/5040 - 5600/5040 = 2835 - 5600/5040 = -2765/5040
After reducing the fraction, the answer is -79/144

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