Question

Rajat carried two types of pens with him. The ratio of cost of Pen A: Pen B was 10:4. There were two pens
of type B with him and the average cost of all the three pens together was Rs 60/-. Find the cost of Pen A.​

Answer 1

Answer:

Given :

$\textsf{No. of pens = 3 }$

$\textsf{There is two types of pen}$

$\textsf{Pen A is one}$

$\textsf{Pen B is two }$

$\sf{They \:are \:in \:ratio\: = 10:4 \:= 10:(4\times2) = 10:8}$

Taken , 8 because there is two pens .

$\textsf{Average cost of all three pens together = Rs 60/-}$

To find :

$\textsf{Cost of Pen A }$

Concept :

Let the cost of Pen A be x

To find the cost of Pen A first find the total cost of all pen . Then , find the cost of x . And then multiply the value of x with 10 .

So , the cost of all pens -:

$\sf\implies{3\times60}$

$\sf\implies{Rs\:180/-}$

So , now find the cost of Pen A by this equation -:

$\sf\boxed{10x+8x=Rs\:180/-}$

Solution :

$\sf\implies{10x+8x=Rs\:180/-}$

$\sf\implies{18x=Rs\:180/-}$

$\sf\implies{x=\dfrac{Rs\:180/-}{18}}$

$\sf\implies{x=10}$

So , the value of x is 10 .

Cost of Pen A -:

$\sf\implies{Ca=10\times10}$

$\sf\implies{Ca=Rs\:100/-}$

So , the cost of Pen A is Rs 100/- .

Extra :

Cost of Pen B -:

$\sf\implies{Cb=8\times10}$

$\sf\implies{Cb=Rs\:80/-}$

One pen = 80÷2 = Rs 40/- .

So , cost of Pen B is Rs 80/- . And it's one pen is Rs 40/- .

Answer :

Cost of Pen A = Rs 100/-