1/4 + 11/12 + m= 2 what number is the m

The administrator of a large assisted living facility wanted to know the average age of the residents living at the facility. he randomly selected 12 residents and determined their age, listed here: 80, 65, 75, 83, 68, 73, 88, 79, 94, 72, 79, 68 what's the average age of the sample of residents? a. 79 years old b. 68 years old c. 75 years old d. 77 years old

Could somebody me with this radical simplification?

The probability that a tutor will see 0, 1, 2, 3, or 4 students is given below determine the probability distribution's missing value.