# 8 balls one is heavier or lighter

But I'm interested in a variation of this problem. How will you find which ball is different? Weigh abd against egh. Put the two groups that have the same number onto the scale, and if either one is heavier or lighter (depending if the extra ball is heavier or lighter) that one contains the odd ball out. Answer: Label the balls â¦ g and h are normal balls. Take 6 balls and split them into 2 groups of 3 balls each. Now you know the heavy ball is one of two possibilities. You donât know that the defective one is heavier or lighter than other balls. Else the heavier one will tilt the balance on its side. You are also given a two-pan balance to use. RickB. 2 weighings to find the slightly heavier ball. Clear the scale and place one of the 2 balls in one scale and another ball from the remaining group on the other. There are twelve identical-looking balls, but one is either heavier or lighter than the other eleven. You have 12 identical balls. if they balance, then the other ball is the lighter or heavier one, if not that is the one ! You have 12 balls all look identical (in shape, color etc.). In this brain teaser you are given 12 identical balls and a scale except that 1 ball is slightly heavier or lighter than the other 11 balls. In this case, the counterfeit is one of 1, 2, and 3. Lv 7. We need to find it in no more than 3 weighings. Weigh {10} and {11}. 2) abc < def One of a, b, c could be a lighter ball; or one of d, e, f could be a heavier ball. From these three balls, discard one of them and choose the other two to weigh. - 7179951 12 golf ball riddle 12 golf balls all appear same-one weighs slightly different-heavier or lighter scales and 3 uses. Which one â¦ How many times if you don't know whether the ball is heavier or lighter? If they are not equal, the ball that matches the group as heavier or lighter, is the heavier or lighter ball. You need to find that one using no more than some specified number of weighings. If they are the same, the odd ball is in the reserved 2, if they differ the odd ball is one of the two you weighed. You have a set of balance scales which will give 3 possible readings: Left = Right, Left > Right, or; Left < Right (ie Left and Right have equal weight, Left is Heavier, or Left is Lighter). If the scale balances, the third ball is the oddball. How can you determine which is the odd ball and find out whether this ball is heavier or lighter than the others using only three weighings with a balance? If the genuine balls are heavier, then the counterfeit is a light ball, and vice-versa. What's the fewest number of times you'd have to use the balance to find out which ball is different, and if it is heavier or lighter than the others. Unless you know whether it's heavier or lighter, two weighings looks impossible.The maximum you can reduce possibilities by is a factor of three per weighing. Split the n balls into 3 groups of O/3, or as close as possible (at least two of the groups will have the same # of balls). You have a balance and you can measure with it only 3 times to determine the different ball. If the 3 balls from C didn't match the 3 balls from A in your second weighing, you now know if the unusual ball is too light or too heavy. 8 Balls One Is Heavier. At one point the scale will balance. You have 12 balls identical in size and appearance but 1 is an odd weight (could be either light or heavy). If one is heavier than the other, then you know that group contains the bomb. Otherwise, the third ball is the bomb. Case B: the pans are not in balance. case 2. If the two balls being weighed balance, the other not weighed is the lighter ball. Many bowling pro shops will let you try bowling balls of different weights to determine which one is best for you. One of them is slightly lighter or heavier. Can you help? If one of the two balls is lighter than the other one being weighed, it is the lighter ball. Total 2 tries. All of them look similar and feel the same. There are 8 balls. If a group is known to be heavier or lighter, it can be determined by weighing one ball against another. You cannot reduce 16 to 1 in two weighings. If not, then the third group contains the bomb. Interview question for Intern.8 balls the same size; one is heavier than others; how many times do you need to use a balance scale to find the ball? Light bulb in a room; three switches outside the room; can only go into the room once; how do you find which switch goes to the light? You can also test for yourself by using house balls of different weights, although it's important to note a house ball will feel heavier than a custom-drilled ball of the same weight. Weighing Pool Balls Puzzle . Case 1. if they are both equal in weight, compare the last 2 balls - one will be heavier. Step 1: Choose 6 balls at random, and put 3 on each side of the balance. Weigh {8, 9} and {10, 11} (Note: 8 is surely not fake) balance - If they balance, we know 12 is the fake one. If the two balls balance each other, then the heavier one is discarded third balls. Arash. DETERMINE WHICH IS THE BALL 1-12 Submitted: 12 years ago. However, one of the balls is heavier or lighter. A terrorist has implanted one of the balls with explosives, but they add such a small amount that no one can tell the difference. All of them have same weight except one defective ball. Just weigh it with any other ball and figure out if it is lighter or heavier. 1 decade ago. \$2\$. Then, you take the group which contains the bomb and weigh two of its balls against each other. In this particular example we have 12 coins, one of them is forged and may be heavier or lighter, we donât known which. You have 9 billiard balls, and a weighing balance. If they are equal, the third ball is the heavier or lighter ball. If one of the groups is heavier than the other group, pick 2 balls from the heavier group and use the scale to weigh them. 8 balls with him. If it's not completely clear how we can make the assumption that the bad coins is in group 7,8 & 9 when the scales balance, remember we know there is a bad coin, there has to be, we have eliminated the other two groups, it â¦ Outcome 1.1: The balls balance. I know that you must weigh more than one ball on each scale and that you can get information from the good batch of balls. If one is different, we don't know whether it is heavier or lighter than the others. If either group of 3 balls is heavier, take 2 balls from the heavier side. A third weighing, comparing ball 4 with a genuine one will tell whether it is lighter or heavier. 8 balls weigh the same. Then take the heavier group of four and divide them again, two on one side of the scale, and two on the other. Step 1. compare 2 groups of three balls. Click hereðto get an answer to your question ï¸ 15.Two balls of different masses (one lighter and other heavier) are thrown vertically upward with the same initial speed. one ball is either heavier or lighter than the rest. Separating Heavier from the Lighter Balls. Source(s): https://owly.im/a0fsj. Split the balls into 4 groups of 3. A second comparison will determine whether the oddball is lighter or heavier than the other two balls. If they balance, 9 is fake (heavier). So, in two weighings, the maximum reduction of possibilities is a factor of 9 If you have 8 balls, and do not know whether the odd one out is heavier or lighter, you have sixteen possibilities. Scale and 8 balls one is heavier or lighter one of the two balls being weighed, it can be by. Do it? thanks of equal size only 3 times to determine which is the one! 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