Add 35/42 and 20/21, Solve 35/42 + 20/21 as a fraction

Add 35/42 and 20/21

35/42 + 20/21 is 25/14.

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,
35/42 = 35 × 1/42 × 1 = 35/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42
Add the two like fractions:
35/42 + 40/42 = 35 + 40/42 = 75/42
75/42 simplified gives 25/14
So, 35/42 + 20/21 = 25/14
In mixed form: 111/14

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