Subtract 70/42 from 70/45, Solve 1 25/45

Subtract 70/42 from 70/45

1^st number: 1 25/45, 2^nd number: 1 28/42

70/45 - 70/42 is -1/9.

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,
70/45 = 70 × 14/45 × 14 = 980/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
70/42 = 70 × 15/42 × 15 = 1050/630
Subtract the two like fractions:
980/630 - 1050/630 = 980 - 1050/630 = -70/630
After reducing the fraction, the answer is -1/9

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