Add 42/80 and 15/12, Solve 42/80 + 1 3/12 as a fraction

Add 42/80 and 15/12

1^st number: 42/80, 2^nd number: 1 3/12

42/80 + 15/12 is 71/40.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240
Likewise, for the 2nd fraction, since 12 × 20 = 240,
15/12 = 15 × 20/12 × 20 = 300/240
Add the two like fractions:
126/240 + 300/240 = 126 + 300/240 = 426/240
426/240 simplified gives 71/40
So, 42/80 + 15/12 = 71/40
In mixed form: 131/40

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