In a nursery class of 18 pupils, the average is 4
years. what is the sum of the ages of pupils?

The sum of ages of all 18 pupils in the class = 81

Step-by-step explanation:

Total number of pupil in the class =  18

Average of years in the class =

Now,

⇒Average of sum of ages  in the class = 4.05

Let us assume the sum of ages of all students in the class = m

By the formula for AVERAGE:

or, m =  18 x 4.5 = 81

Hence, the sum of ages of all 18 pupils in the class = 81

81

Step-by-step explanation:

Average = 4.5 years

Total = 18

Sum = 4.5 × 18 = 81

answer: all of the odd numbers were opened

the first person was the one that was opening all of the lockers. since one is odd, this causes all of the odd number lockers to be opened in the end.

12r - 8 - 12

you have to combine like terms. below i have bolded the like terms:

12r - 8 - 12

together it combines to:

12r - 20

hope this !