Question

A purchases 5 chairs and 2 tables for Rs 1625. B purchased 2 chairs and 1 table for Rs 750 . The cost per chair and per table respectively are ....

Answer 1

Let chairs be C and tables be T
So There are two persons A and B
For A..........  5C + 2T = 1625

For B........... 2C + T = 1500

Now for subtracting multiply B by 2 and subtract 2 from 1 we get
cost per chair is 125 Rs and
cost per table is 500 Rs

Answer 2

Let the cost of one table = Rs. x
     the cost of one chair = Rs. y

cost of 5 chairs and 2 tables for Rs 1625
or 5y + 2x = 1625   --------------(1)
cost of 2 chairs and 1 table for Rs 750
or 2y + x = 750   -----------------(2)

(now you have two equations and two variables. You can solve them in any method you want.)
from equation (2), we can write that,
x = 750-2y
putting in equation (1),
5y + 2(750-2y) = 1625
⇒ 5y + 1500 - 4y = 1625
⇒ 5y - 4y = 1625 - 1500
⇒ y = 125 (cost of one chair)
   x =750 - 2y = 750 - 2×125 = 750 - 250 = 500 (cost of one table)

Hence, cost per chair is Rs. 125 and cost per table is Rs. 500.