Add 15/12 and 63/40, Solve 1 3/12 + 1 23/40 as a fraction

Add 15/12 and 63/40

1^st number: 1 3/12, 2^nd number: 1 23/40

15/12 + 63/40 is 113/40.

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,
15/12 = 15 × 10/12 × 10 = 150/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
63/40 = 63 × 3/40 × 3 = 189/120
Add the two like fractions:
150/120 + 189/120 = 150 + 189/120 = 339/120
339/120 simplified gives 113/40
So, 15/12 + 63/40 = 113/40
In mixed form: 233/40

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