Add 42/15 and 90/20, Solve 2 12/15 + 4 10/20 as a fraction

Add 42/15 and 90/20

1^st number: 2 12/15, 2^nd number: 4 10/20

42/15 + 90/20 is 73/10.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 20 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 15 × 4 = 60,
42/15 = 42 × 4/15 × 4 = 168/60
Likewise, for the 2nd fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60
Add the two like fractions:
168/60 + 270/60 = 168 + 270/60 = 438/60
438/60 simplified gives 73/10
So, 42/15 + 90/20 = 73/10
In mixed form: 73/10

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