There are 9 ball bearings. They are all exactly the same in every way exept that one of them is lighter that the rest. You have an old balace scale. By putting ball bearings into the scale only twic how can you tell which is the lighter one.
2007-03-13 06:10:26 · 6 answers · asked by Anonymous in Entertainment & Music ➔ Jokes & Riddles
first you divide it into 2 groups, one w/ 5 and the other w/ 4. Weigh them. Divide that into 2 groups again and then check for the lighter one. Wait I'm out of tries! Oh, well i got this far...but i would still like to know the answer!
2007-03-13 06:15:16 · answer #1 · answered by nicki2400 2 · 0⤊ 0⤋
You need not even put them twice, you can find out the lighter one in one go itself. Just put 4 ball bearings on either side of the balance - adjust the Balance, by changing the bearings till both sides equal. Then you will be left with the lighter one with you.
2007-03-13 13:17:28 · answer #2 · answered by Alrahcam 4 · 0⤊ 0⤋
First put 4 each into the 2 pans. If they equalize the remaining is the lighter. Otherwise, find which group has gone upwards. Divide them into 2 equal groups and weigh them again.
Find which group is lighter. Then, take out one each from 2 pans. If the remaining equalize, the ball from the lighter group is required one. Otherwise the ball on the lighter pan is required one.
2007-03-13 13:22:03 · answer #3 · answered by saptaswa2 2 · 0⤊ 0⤋
divide the balls into 3 groups of 3. weigh any two groups. if they are not balanced the lighter ball is on the side that goes up. if they are balanced the ball is in the remaining set.
take the set you know the ball is in. and weigh any two of the balls in that set. the scale will either reveal that one of the balls on the scale is the lighter on, or if they are balanced it is the remaining ball.
2007-03-13 17:55:51 · answer #4 · answered by just curious (A.A.A.A.) 5 · 1⤊ 0⤋
the best answer would be place one ball bearing on one side of the scale, and place the other on the other side and see if they balance. the scales should be blanced as long as there are the same ammount of bearings on either side of the scale... until you place the lighter one on, then you know that the last one you put on was the lighter one.
2007-03-13 13:21:38 · answer #5 · answered by eveningdin 4 · 0⤊ 0⤋
divide into three groups of three balls each
weigh two of them... if the scales balance the light ball is in the unweighed group, if the scales do not balance the light ball is in the lighter group
now you know which group it is in
discard the other two groups
weigh two of the three balls left
if scales balance it is the one not weighed... if the scales do not balance it is the light ball on the scales
2007-03-13 13:23:02 · answer #6 · answered by ? 3 · 2⤊ 0⤋