Add 40/42 and 12/9, Solve 40/42 + 1 3/9 as a fraction

Add 40/42 and 12/9

1^st number: 40/42, 2^nd number: 1 3/9

40/42 + 12/9 is 16/7.

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,
40/42 = 40 × 3/42 × 3 = 120/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126
Add the two like fractions:
120/126 + 168/126 = 120 + 168/126 = 288/126
288/126 simplified gives 16/7
So, 40/42 + 12/9 = 16/7
In mixed form: 22/7

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