Subtract 3/18 from 40/84, Solve 40/84

Subtract 3/18 from 40/84

40/84 - 3/18 is 13/42.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 84 × 3 = 252,
40/84 = 40 × 3/84 × 3 = 120/252
Likewise, for the 2nd fraction, since 18 × 14 = 252,
3/18 = 3 × 14/18 × 14 = 42/252
Subtract the two like fractions:
120/252 - 42/252 = 120 - 42/252 = 78/252
After reducing the fraction, the answer is 13/42

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