Add 45/12 and 45/40, Solve 3 9/12 + 1 5/40 as a fraction

Add 45/12 and 45/40

1^st number: 3 9/12, 2^nd number: 1 5/40

45/12 + 45/40 is 39/8.

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,
45/40 = 45 × 3/40 × 3 = 135/120
Add the two like fractions:
450/120 + 135/120 = 450 + 135/120 = 585/120
585/120 simplified gives 39/8
So, 45/12 + 45/40 = 39/8
In mixed form: 47/8

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