Add 90/42 and 80/21, Solve 2 6/42 + 3 17/21 as a fraction

Add 90/42 and 80/21

1^st number: 2 6/42, 2^nd number: 3 17/21

90/42 + 80/21 is 125/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
90/42 = 90 × 1/42 × 1 = 90/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
80/21 = 80 × 2/21 × 2 = 160/42
Add the two like fractions:
90/42 + 160/42 = 90 + 160/42 = 250/42
250/42 simplified gives 125/21
So, 90/42 + 80/21 = 125/21
In mixed form: 520/21

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