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osirvics

Guest

Arithmetic Progression

if 3x, y, 18 are in A.P find x and y?
i tried... please i need a help. thanks

Bob

Administrator

Registered: 2010-06-20

Posts: 10,643

Re: Arithmetic Progression

hi osirvics

Welcome to the forum.

Not enough information for a unique solution

The difference between the second and the first term = the difference between the third and the second, so:

y - 3x = 18 - y

2y = 3x + 18

Any points on the line will give a solution.

eg.  x = 2, y = 12     AP = 6, 12, 18, ....
       x = 4, y = 15    AP = 12, 15, 18, ...
       x = 3, y = 13.5 AP = 9, 13.5, 18, ... 

Bob

Last edited by Bob (2015-05-29 05:55:25)

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