Subtract 18/9 from 9/40, Solve 9/40

Subtract 18/9 from 9/40

1^st number: 9/40, 2^nd number: 2 0/9

9/40 - 18/9 is -71/40.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 9 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 40 × 9 = 360,
9/40 = 9 × 9/40 × 9 = 81/360
Likewise, for the 2nd fraction, since 9 × 40 = 360,
18/9 = 18 × 40/9 × 40 = 720/360
Subtract the two like fractions:
81/360 - 720/360 = 81 - 720/360 = -639/360
After reducing the fraction, the answer is -71/40

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