Question

James bought 5 each of two kinds of CFL
bulbs for 100 rupees. The price of the
cheaper lamp is 85 rupees a piece. What
is the price of one of the costlier kind?

Answer 1

The correct question is given below-

James bought 5 each of two kinds of CFL  bulbs for 1000 rupees. The price of the  cheaper lamp is 85 rupees apiece. What is the price of one of the costlier kind?

The answer is 115 rupees.

Given:

James bought 5 each of two kinds of CFL  bulbs for 1000 rupees.

The price of the cheaper one is 85 rupees per piece.

To Find:

The price of the costlier CFL.

Solution:

The cost of 1 piece of the cheaper CFL is 85 rupees, so the price of 5 pieces will be $=85*5$

                      $=425$ rupees

Now,

Let the cost of a piece of the costlier CFL be x

So, the cost of 5 pieces of the costlier $=5x$

We are also given,

The cost of 5 pieces of the cheaper CFL and 5 pieces of the costlier CFL is 1000 rupees.

So,

$425+5x=1000$

         $5x=1000-425$

         $5x=575$

          $x=\frac{575}{5}$

          $x=115$

Hence, the cost of one piece of costlier CFL is 115 rupees.