Rounding Off Numbers

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not rounded numerals equals 24.




Similar Math Riddles

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0 0 0 = 6
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You can use any mathematical symbols in the space provided to make all above algebraic expressions true.

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The third house is 60 meters apart from the first house.
The fourth house is 40 meters apart from the second house.
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How much did the widow receive?

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Can you answer the question?

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Can you find out the number of chocolates they have right now?

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