A box turtle and a map turtle escape from the reptile house of the Kalamazoo Zoo. The box turtle is older than the map turtle. The average age of the turtles remaining at the zoo after the escape is 1 year less than the average age before the escape.
What is the age of the escaped box turtle?
This is an old one but it got overlooked.
I am assuming that the stem and leaf plot shows the ages of all the turtles at the zoo.
The sum of the ages is 440 and there are 20 turtles so the average age is 22 years.
After two escape the average age becomes 21
so the total of all the ages of the remining turtles is 21*18 = 378 years.
440 - 378 = 62
The sum of the ages of the 2 escaped turtles is 62
The only two turtles whose ages add to 62 are 26 and 36 years old. The box tutel is the oldest
The escaped box turtle is 36 years old!
What an unusual question :)