Question

What value of k causes the terms 5, 2k, 13 to form an arithmetic sequence?

2
4
9/2
13/4

Answer 1

Answer:

$k=\frac{9}{2}$

Step-by-step explanation:

The  given sequence is

$5,2k,13$

For the sequence to be arithmetic, then

$2k-5=13-2k$

We group similar terms to get;

$2k+2k=13+5$

$4k=18$

Divide both sides by 4;

$k=\frac{18}{4}$

Simplify;

$k=\frac{9}{2}$

Answer 2

Answer:

The correct answer is 3rd option 9/2

Step-by-step explanation:

From the given sequence, 5, 2k, 13

Which are in AP.

We can consider a₁ = 5 , a₂ = 2k and a₃ = 13

To find the value of k

We have,

a₂ = (a₁ + a₃)/2

Here,

2k = (5 + 13)/2 = 18/2 = 9/2

Therefore the correct answer is option 3

9/2