Add 9/42 and 72/20, Solve 9/42 + 3 12/20 as a fraction

Add 9/42 and 72/20

1^st number: 9/42, 2^nd number: 3 12/20

9/42 + 72/20 is 267/70.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
9/42 = 9 × 10/42 × 10 = 90/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Add the two like fractions:
90/420 + 1512/420 = 90 + 1512/420 = 1602/420
1602/420 simplified gives 267/70
So, 9/42 + 72/20 = 267/70
In mixed form: 357/70

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