What is the sum of 1/6, 2/3, and 1/4

1/6 + 2/3 + 1/4

1) Get the least common denominator
multiple of 6: 6, 12, 18, 24
multiple of 3: 3, 6, 9, 12
multiple of 4: 4, 8, 12

LCD is 12

1/6 * 2/2 = 2/12
2/3 * 4/4 = 8/12
1/4 * 3/3 = 3/12

2) Add the numerators and put the sum above the LCD.
2/12 + 8/12 + 3/12 = 13/12

3) Simplify the fraction.
13/12 is an improper fraction, it can only be simplified resulting to a mixed fraction.

13/12 = 1 1/12

1/6 + 2/3 + 1/4 = 1 1/12