Question

suppose you wish to buy a pencil , a notebook and a pen .the prices of these are in a.p. such that the sum of prices of these three things is 27 and sum of square of their prices is 341 . find price of each thing.

Answer 1

let the prize of pencil=a-d

let the prize of notebook = a

let the price of pen be  = a+d

sum=27

a-d+a+a+d=27

3a=27

a=9

(a-d)²+a²+(a+d)²=341

3a²+2d²=341

243+2d²=341

2d²=98

d=7

pencil=2

notebook=9

pen = 16

Answer 2

The prices are in A. P. [Given]

Let price of pencil= a- d,

Price of notebook= a,

Price of pen= a+d

As, a-d+a+a+d= 27:

3a = 27:

a = 9,

And, (a-d)^2+ (a)^2+ (a+d)^2 = 341:

We get d= 7

Therefore, prices of pencil, notebook and pen are Rs. 2, Rs. 9 and Rs. 16 resoectively.