10 Pounds of Flour

You have a big bag of flour, two 5lbs weights, and an inaccurate balance scale. How can you measure exactly 10lbs of flour?

Put both weights on one side, then fill the other side with flour so that the scale balances out. Then remove the weights and replace them with flour so that the balance scale is balanced again. The amount of flour you put there is exactly 10lbs.

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  1. My answer would be to take out my shoelaces, find a couple of sticks, make a balance with my shoes as the little plates, put the two fives on one side, and put flour on the other until it balances out.

  2. I don’t understand. U said, the scale is inaccurate. If u balance it out in the first time, your flour is not equal to 10lbs.
    My solution is u put 5 weight in two different sides. Now u will see the scale tilt into one side because of the scale is broken. Then u add some flour to one side to balance it out, move the weight from another side to this side. Now you will have two of 5 weight and some flour in one side and nothing in another. Then when you pour the flour to balance this out, you will have exactly 10lbs of flour.

    1. Hi Sassaya. It is correct that the flour on the second side may not be 10lbs. Still, the flour on the first side will weigh the same as the 2 weights we placed there initially.

  3. You explained that weird, but after rereading this six times I get what you’re saying. You are saying to place two weights on one side and fill the other side with flour until the scale reads balanced, then Pour flour where the weights were UNTIL the scale balances out again. My answer to this was to simply measure one weight to the other and calculate out the difference to mentally balance the balance