Subtract 80/40 from 20/30, Solve 20/30

Subtract 80/40 from 20/30

1^st number: 20/30, 2^nd number: 2 0/40

20/30 - 80/40 is -4/3.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 30 × 4 = 120,
20/30 = 20 × 4/30 × 4 = 80/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
80/40 = 80 × 3/40 × 3 = 240/120
Subtract the two like fractions:
80/120 - 240/120 = 80 - 240/120 = -160/120
After reducing the fraction, the answer is -4/3

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