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Find ‘k’ if 2 k- 1, 7, 11are in A.P.

1 Answer

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Given:

• 2k -1 , 7 and 11 are in AP .

To find :

• The value of k .

Solution :

• As we know that , In AP common difference is same .

• b - a = c - b

=> 2b = a + c

Here :

• a = 2k-1

• b = 7

• c = 11

=> 2 (7) = 2k-1+11

=> 14 = 2k+10

=> 2k = 14-10

=> 2k = 4

=> k = 4/2

=> k = 2 .

Hence ,the value of k is 2 .

Hope it will help you.

Regards.

User Megan Sime
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