
01/31/2005, 11:44 AM
#4677
Originally Posted by ChickDance
Chick is going to recite to her class the numbers between 1 and 100, including perhaps 1 and 100.
Chick will leave a space of about 8 seconds between each one. So, the first number she will give her class, for example, might be "3," then "4," then "28," then "52."
When Chick is through reciting all the numbers but one, she's going to ask her class which one she left out.
Her class can't use a pencil and paper or write anything down. When Chick is done she has given her class not a hundred numbers, but ninetynine.
Chick's class job is to tell her which one number she didn't give her class. How would her class solve this problem most efficiently?
Sorry to get into this so late. How do you define efficient? do the kids get a calculator? how many kids in the class? if there are more than 5 kids in the class, have each kid represent a group of 20 numbers, using their fingers and toes (if there are 10 kids, then 10 for each kid, using fingers only). I assume efficient also means 'minimal thinking'. Therefore, adding the numbers together and subtracting them from the expected sum is not as efficient as "taking a finger down".


