Subtract 7/40 from 45/12, Solve 3 9/12

Subtract 7/40 from 45/12

1^st number: 3 9/12, 2^nd number: 7/40

45/12 - 7/40 is 143/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 12 × 10 = 120,
45/12 = 45 × 10/12 × 10 = 450/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
7/40 = 7 × 3/40 × 3 = 21/120
Subtract the two like fractions:
450/120 - 21/120 = 450 - 21/120 = 429/120
After reducing the fraction, the answer is 143/40
In mixed form: 323/40

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