Here’s and example of a SMART MATH problem for AVERAGES.
Problem
The captain of a certain team of 11 players is 25 years old and the vice captain is 3 years older. If the ages of these two players are excluded, the average age of the remaining players is 1 year less then the average age of the whole team. What is the average age of the whole team?
- 21.5 years
- 22 years
- 22.5 years
- 23 years
- 25 years
The Usual Method
Total age of captain and vice captain = 25 + (25 + 3) = 53 years.
Let the average age of all players be ‘x’ years.
Hence, total age of 11 players = 11x years
years
Hence, average age of the whole team = 22 years
(Ans: 2)
Estimated Time to arrive at the answer = 45 seconds.
Using Technique
[contentblock id=google-adsense-post]
For 9 players, if the average age goes below by 1 year, the total reduction in age = 9 years. Since, the average age of the 9 players gets reduced due to not including the ages of captain and vice captain. Hence, the captain and vice captain’s age contribute to the reduction of 9 years. Total age of captain and vice captain = 25 + 28 = 53 years.
53 – 9 = 44 years will be the age of 2 players of the team. Hence, average age of the team = years
(Ans: 2)
Estimated Time to arrive at the answer = 15 seconds.
[starrater tpl=10]
[contentblock id=smartmath-blockquote]