1999 AMC 8 Problems/Problem 13
Revision as of 18:07, 4 November 2012 by Firestarly (talk | contribs)
problem
The average age of the 40 members of a computer science camp is 17 years. There are 20 girls, 15 boys, and 5 adults. If the average age of the girls is 15 and the average age of the boys is 16, what is the average age of the adults?
solution
The answer is (C). First, find the total amount of the girl's ages and add it to the total amount of the boy's ages. It equals 540. You have to see what can give you 17 when you divide by 40. So, you do Then you do
The 5 adult's ages should add up to 140. You then do
. So, the answer is (C).
see also
1999 AJHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 12 |
Followed by Problem 14 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AJHSME/AMC 8 Problems and Solutions |