There are 20 children at a library. Six of the children have a averahe age of 5 years. The remaining children have a sverage age of 8 years. What is the average age of the children at the library?​

The average age of the children at the library is 7.1 years.

Step-by-step explanation:

Given,

Out of 20 children, six of the children have an average age of 5 years,

Thus, the sum of the ages of 6 students = 5 × 6 = 30

( Total sum of observations = Their Average × Total numbers of the observations )

Now, remaining students = 20 - 6 = 14,

Since, the remaining children have an average age of 8 years.

Thus, the sum of the ages of 14 students = 14 × 8 = 112,

Total sum of the ages of 20 students = 30 + 112 = 142

=142/20

= 7.1 years

The average is 7.1 years!

Step-by-step explanation:

6 children = average of 5 years

14 children = average of 8 years

x + 107

step-by-step explanation:

let's say that the number he had before the mistake was x. then, he will have 107 dollars more than this, so the answer is x + 107.