Add 36/21 and 40/12, Solve 1 15/21 + 3 4/12 as a fraction

Add 36/21 and 40/12

1^st number: 1 15/21, 2^nd number: 3 4/12

36/21 + 40/12 is 106/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
36/21 = 36 × 4/21 × 4 = 144/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
40/12 = 40 × 7/12 × 7 = 280/84
Add the two like fractions:
144/84 + 280/84 = 144 + 280/84 = 424/84
424/84 simplified gives 106/21
So, 36/21 + 40/12 = 106/21
In mixed form: 51/21

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