Subtract 21/6 from 40/75, Solve 40/75

Subtract 21/6 from 40/75

1^st number: 40/75, 2^nd number: 3 3/6

40/75 - 21/6 is -89/30.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 6 is 150

Next, find the equivalent fraction of both fractional numbers with denominator 150
For the 1st fraction, since 75 × 2 = 150,
40/75 = 40 × 2/75 × 2 = 80/150
Likewise, for the 2nd fraction, since 6 × 25 = 150,
21/6 = 21 × 25/6 × 25 = 525/150
Subtract the two like fractions:
80/150 - 525/150 = 80 - 525/150 = -445/150
After reducing the fraction, the answer is -89/30

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