Subtract 84/45 from 40/42, Solve 40/42

Subtract 84/45 from 40/42

1^st number: 40/42, 2^nd number: 1 39/45

40/42 - 84/45 is -32/35.

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,
40/42 = 40 × 15/42 × 15 = 600/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
84/45 = 84 × 14/45 × 14 = 1176/630
Subtract the two like fractions:
600/630 - 1176/630 = 600 - 1176/630 = -576/630
After reducing the fraction, the answer is -32/35

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