Subtract 12/9 from 9/40, Solve 9/40

Subtract 12/9 from 9/40

1^st number: 9/40, 2^nd number: 1 3/9

9/40 - 12/9 is -133/120.

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,
12/9 = 12 × 40/9 × 40 = 480/360
Subtract the two like fractions:
81/360 - 480/360 = 81 - 480/360 = -399/360
After reducing the fraction, the answer is -133/120

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