There might be a variety of averages for the 12 boys.
Answer:
Step-by-step explanation:
Step 1: Convert into improper fractions
Step 2: Find least common denominator and find equivalent fractions
Step 3 : Do the required operation

Least common denominator of 2 , 4 = 4

Answer: 
Step-by-step explanation:
Given: The total number of ways of to choose 3 contestants out of 7 (including me and my friend)=35..................> Total outcomes.
Favorable outcomes = 2
Then the probability that me and my friend are both chosen =
Thus , the probability that me and my friend are both chosen =
For the last one is the pi sign and 2.333
You just put the numbers in the formula 3x30 = 90 km