Add 45/42 and 21/9, Solve 1 3/42 + 2 3/9 as a fraction

Add 45/42 and 21/9

1^st number: 1 3/42, 2^nd number: 2 3/9

45/42 + 21/9 is 143/42.

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,
45/42 = 45 × 3/42 × 3 = 135/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
21/9 = 21 × 14/9 × 14 = 294/126
Add the two like fractions:
135/126 + 294/126 = 135 + 294/126 = 429/126
429/126 simplified gives 143/42
So, 45/42 + 21/9 = 143/42
In mixed form: 317/42

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