Subtract 10/15 from 40/80, Solve 40/80

Subtract 10/15 from 40/80

40/80 - 10/15 is -1/6.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 15 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
40/80 = 40 × 3/80 × 3 = 120/240
Likewise, for the 2nd fraction, since 15 × 16 = 240,
10/15 = 10 × 16/15 × 16 = 160/240
Subtract the two like fractions:
120/240 - 160/240 = 120 - 160/240 = -40/240
After reducing the fraction, the answer is -1/6

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