Subtract 84/45 from 1/42, Solve 1/42

Subtract 84/45 from 1/42

1^st number: 1/42, 2^nd number: 1 39/45

1/42 - 84/45 is -129/70.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
1/42 = 1 × 15/42 × 15 = 15/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
84/45 = 84 × 14/45 × 14 = 1176/630
Subtract the two like fractions:
15/630 - 1176/630 = 15 - 1176/630 = -1161/630
After reducing the fraction, the answer is -129/70

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