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Three numbers are in the ratio of 1:2:4. If 3 is added to the first and 8 is subtracted from the third, the new numbers will be the first and third terms of an A.P., whose second term is the second number. Find the original numbers.​

User Stirman
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1 Answer

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9514 1404 393

Answer:

5, 10, 20

Explanation:

Suppose the three numbers are x, 2x, and 4x. Then they have the required ratios. After the transformation, we have ...

((x+3) +(4x -8))/2 = 2x . . . . . 2nd term is average of 1st and 3rd

5x -5 = 4x ⇒ x = 5

The original numbers are 5, 10, 20.

_____

After the adjustment, the arithmetic sequence is 8, 10, 12.

User Bo Halim
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