Add 21/42 and 45/9, Solve 21/42 + 5 0/9 as a fraction

Add 21/42 and 45/9

1^st number: 21/42, 2^nd number: 5 0/9

21/42 + 45/9 is 11/2.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
45/9 = 45 × 14/9 × 14 = 630/126
Add the two like fractions:
63/126 + 630/126 = 63 + 630/126 = 693/126
693/126 simplified gives 11/2
So, 21/42 + 45/9 = 11/2
In mixed form: 51/2

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