Add 40/21 and 15/18, Solve 1 19/21 + 15/18 as a fraction

Add 40/21 and 15/18

1^st number: 1 19/21, 2^nd number: 15/18

40/21 + 15/18 is 115/42.

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,
15/18 = 15 × 7/18 × 7 = 105/126
Add the two like fractions:
240/126 + 105/126 = 240 + 105/126 = 345/126
345/126 simplified gives 115/42
So, 40/21 + 15/18 = 115/42
In mixed form: 231/42

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