Question

There are 25 students in Mrs. Venetozzi's class at the beginning of the school year, and the average number of siblings for each student is 3. A new student with 8 siblings joins the class in November. What is the new class average for number of siblings?

Answer 1

The new average is `83-: 26 = 3 5/26` exactly

`83-:26 ~~3.192` to 3 decimal places

Explanation:

Assumption: None of the siblings are in that class.

`color(blue)("Original numbers")`

25 students with 3 siblings each gives `25xx3= 75` siblings

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`color(blue)("New numbers")`

1 new student takes the total students to 25+1 = 26

The new total siblings is `75+8 = 83`

The new average is `83-: 26 = 3 5/26` exactly

`83-:26 ~~3.192` to 3 decimal places