Question

If+the+mean+of+first+n+natural+number+is+15,+then+n+=
(a)15
(b)30
(c)14
(d)29

Answer 1

Answer:

• Value of n = (d) 29

Step-by-step explanation:

Let n is the total term of natural numbers.

Therefore, Mean = $\frac{1+2+3+... +n}{n}$ =15

                             ⇒ $\frac{n(n+1)}{2} \frac{1}{n}$    =15

                              ⇒n+1      =    30

                             ⇒n      =    29