Subtract 80/42 from 4/45, Solve 4/45

Subtract 80/42 from 4/45

1^st number: 4/45, 2^nd number: 1 38/42

4/45 - 80/42 is -572/315.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
4/45 = 4 × 14/45 × 14 = 56/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
80/42 = 80 × 15/42 × 15 = 1200/630
Subtract the two like fractions:
56/630 - 1200/630 = 56 - 1200/630 = -1144/630
After reducing the fraction, the answer is -572/315

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