Subtract 9/3 from 20/40, Solve 20/40

Subtract 9/3 from 20/40

1^st number: 20/40, 2^nd number: 3 0/3

20/40 - 9/3 is -5/2.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 3 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
20/40 = 20 × 3/40 × 3 = 60/120
Likewise, for the 2nd fraction, since 3 × 40 = 120,
9/3 = 9 × 40/3 × 40 = 360/120
Subtract the two like fractions:
60/120 - 360/120 = 60 - 360/120 = -300/120
After reducing the fraction, the answer is -5/2

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