Subtract 21/75 from 40/80, Solve 40/80

Subtract 21/75 from 40/80

40/80 - 21/75 is 11/50.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 75 is 1200

Next, find the equivalent fraction of both fractional numbers with denominator 1200
For the 1st fraction, since 80 × 15 = 1200,
40/80 = 40 × 15/80 × 15 = 600/1200
Likewise, for the 2nd fraction, since 75 × 16 = 1200,
21/75 = 21 × 16/75 × 16 = 336/1200
Subtract the two like fractions:
600/1200 - 336/1200 = 600 - 336/1200 = 264/1200
After reducing the fraction, the answer is 11/50

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