Question

You have 8 balls. One of them is defective and weighs less than others. You have a balance to measure balls against each other. In 2 weighing round, how do you find the defective one?Type a message here

Answer 1

Step-by-step explanation:

make three sets of ball

a:2

b:3

c:3

weigh B and c if defective ball is in either of B or c weighing scale will show which lot is lighter(1st measurement complete) then take the lot with defective ball place 1 ball on each side of scale (2nd measurement) and leave 1 out. if defective is on scale you'll know which one of scale is equal the defective is one left out of scale.

if B and c weighing equal that means defective ball is in a and placing 2 balls in scale will give away which one is defective.

Answer 2

Answer

• Make groups of 2, and then weigh them with another group of 2 balls.

• The group containing the defected ball will have a bigger difference from the other groups.

• The thing you will need to notice here is that, as the group containing the defected ball will go down in the weighing balance, the defected ball will have a much greater displacement than the other ball in the same group.

In this way, you can identify the defected ball.