Subtract 30/12 from 45/40, Solve 1 5/40

Subtract 30/12 from 45/40

1^st number: 1 5/40, 2^nd number: 2 6/12

45/40 - 30/12 is -11/8.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 12 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
45/40 = 45 × 3/40 × 3 = 135/120
Likewise, for the 2nd fraction, since 12 × 10 = 120,
30/12 = 30 × 10/12 × 10 = 300/120
Subtract the two like fractions:
135/120 - 300/120 = 135 - 300/120 = -165/120
After reducing the fraction, the answer is -11/8

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