Add 42/15 and 40/42, Solve 2 12/15 + 40/42 as a fraction

Add 42/15 and 40/42

1^st number: 2 12/15, 2^nd number: 40/42

42/15 + 40/42 is 394/105.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
42/15 = 42 × 14/15 × 14 = 588/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
40/42 = 40 × 5/42 × 5 = 200/210
Add the two like fractions:
588/210 + 200/210 = 588 + 200/210 = 788/210
788/210 simplified gives 394/105
So, 42/15 + 40/42 = 394/105
In mixed form: 379/105

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