Add 9/21 and 40/42, Solve 9/21 + 40/42 as a fraction

Add 9/21 and 40/42

9/21 + 40/42 is 29/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
9/21 = 9 × 2/21 × 2 = 18/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
40/42 = 40 × 1/42 × 1 = 40/42
Add the two like fractions:
18/42 + 40/42 = 18 + 40/42 = 58/42
58/42 simplified gives 29/21
So, 9/21 + 40/42 = 29/21
In mixed form: 18/21

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