Add 45/21 and 20/42, Solve 2 3/21 + 20/42 as a fraction

Add 45/21 and 20/42

1^st number: 2 3/21, 2^nd number: 20/42

45/21 + 20/42 is 55/21.

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,
45/21 = 45 × 2/21 × 2 = 90/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
20/42 = 20 × 1/42 × 1 = 20/42
Add the two like fractions:
90/42 + 20/42 = 90 + 20/42 = 110/42
110/42 simplified gives 55/21
So, 45/21 + 20/42 = 55/21
In mixed form: 213/21

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