Question

If arithmetic mean of the values: 2, k. 14 is 7 then the value of k is
(a) 3
(b) 8
(d) 7
(C) 5​

Answer 1

${\bold{\underline{\underline{Answer:}}}}$

${\bold{\therefore k=5}}$

${\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\underline \bold{Given : } \\ \implies A.M \: of \: 2,k,14 = 7\\ \\ \underline \bold{To \: Find: } \\ \implies Value \: of\: k = ?$

• According to given question :

$\bold{Using \: formula \: of \: Arithmetic \: mean : } \\ \implies A.M = \frac{Sum \: of \: all\:given \: numbers}{Total \: no. \: of \: observation} \\\\\bold{Putting\:given\:values:} \\ \implies 7 = \frac{2 + k + 14}{3} \\ \\ \implies 7 \times 3 = 16 + k \\ \\ \implies 21 = 16 + k\\ \\ \implies k = 21 - 16 \\ \\ \bold{\implies k = 5}$

Answer 2

Answer:

So, the value of k = 5

Solution:

Given,

Arithmetic mean of 2, k, 14 = 7

According to the given information,

By using the formula of finding arithmetic mean is:

Arithmetic mean = Sum of all given numbers / Total number of observation

Putting the given values according to the formula of arithmetic mean,

=> 7 = 2 + k + 14 / 3

=> 7 × 3 = 2 + k + 14

=> 21 = 2 + k + 14

=> 21 = 16 + k

=> k = 21 - 16

.°. k = 5