A math problem about weighing scales, a math problem about eight taels of scales

Weigh it three times.

Weigh the first time: Put 4 parts on each side of the balance first.

1. If the balance is balanced, it means that the bad ones are in the other 5.

Weigh the second time: take 3 good balances from the good ones that have been weighed and put them at the left end of the scale, and then take out 3 of the bad ones and put them on the right end of the balance (if it is not balanced, remember whether the right end is high or low, high means that the bad part is lighter than the good part, and vice versa).

1. If the balance is balanced, the bad one is in the remaining two, and it is called the third time: just take one and the good one, then the answer is obvious. 2. If the balance is unbalanced, then the bad one is in those three, called the third time

Take out 2 of them and place them on each end of the scale. If balanced, the answer is obvious. Then the third one is bad.

If it is not balanced, you can judge whether the part is light or focused based on (1), and the answer is obvious.

Second, if the balance is unbalanced, it means that the bad one is among the 8, at this time you should remember which end is light and which end is heavy. Then put 5 good ones on the left end of the scale, take 2 light ends, and put 3 heavy ends on the right end. 1. If the balance is balanced, then take the remaining two light ends and put them at both ends of the balance, if balanced, the answer is obvious.

If it's not balanced, then the bad ones are in these two, and the bad ones are the lighter ones because they are taken from the light end. 2. If the right end is low, it means that the bad ones are in the heavy 3, and the bad parts are heavier, and you will know the answer by weighing them again. If the right end is high, it means that the bad one is in the light 2, and the bad one is lighter, and the answer is obvious again.

In three piles of 661

66 put the balance the same weight Then 1 is a defective product. . .

If it's not the same, then 1 is ** (1 point).

The first 6 is divided into 33 uneven is that there is a defective product uneven is that there is no defective product (point back 2 times) leveling 3 and uneven 3 flat is ** uneven is defective product (point back 2 times) 3 respectively and the first ** weighed different is defective product (point back 3 times).

8 catties of bananas under eight taels of scales = actual catties.

was pitted. Pit money = yuan.

The actual loss of buying catties is 8 catties = the loss of catties.

At least 5 times.

My brother can find that 243 is divided into 3 groups, and each wisdom is 81 parts, so at least the first weighing can determine which part of the ball is in 2 parts of 81 balls.

And so on, split 81 into 3 parts.

So it can be determined at least 5 times.

3 times for the first time, 6 6 weighed, 4 left, if balanced, weigh the remaining 4, 2 times can be solved, if not, look at the next step. The light side.

The second time, 2 2 weighed, 2 left. If it is balanced, weigh the remaining 2, 1 time can be found, if not, look at the next step.

The third time, just call those two, and the light one is it.

The first time, 8 boxes of parts on each side of the scale, 8 parts on the light side, 4 boxes of parts on each side of the balance, 4 boxes on the light side, 2 boxes of parts on the light side, 2 boxes on the light side, 4 boxes on the balance 1 on each side, 1 box on the light side, the box where the three parts were removed, the balance on each side.

First time: 5 boxes 5 boxes.

Situation 1: The same weight, then weigh it in 6 boxes.

The second time: 3 boxes 3 boxes which side is light, the third time which side is called, the third time called: 1 box 1 box.

If it is the same weight, then it is not weighed that the box is less parts, if it is light, it is the light box case two: if the first time is weighed, there is light and heavy, and the light one is weighed the second time: 2 boxes 2 boxes Which side is light, the third time is called which side, if the same, it is not weighed that box is less parts.

The third time: 1 box 1 box, and it was weighed out.

It takes 3 times in total.

5 1+2+3+4=10 +75, +78, +79+ =80, +81, +82, +83, +84, +86, +88 10 data 5

36kg, 39kg, 42kg, 43kg, 44kg Cheng write. by the title.

81- substitution =78- 78-(81- )Keyland-3 solution group = Na-3 + 75 solution.

36 = 39, then Dong Liang macro = 42 = 43 = 44