Add 40/21 and 12/18, Solve 1 19/21 + 12/18 as a fraction

Add 40/21 and 12/18

1^st number: 1 19/21, 2^nd number: 12/18

40/21 + 12/18 is 18/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
40/21 = 40 × 6/21 × 6 = 240/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126
Add the two like fractions:
240/126 + 84/126 = 240 + 84/126 = 324/126
324/126 simplified gives 18/7
So, 40/21 + 12/18 = 18/7
In mixed form: 24/7

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