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

Add 40/42 and 42/15

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

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

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

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

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