Question

Do vibhinn muly vali 35 kalmo ko kul muly 60 rupaya hain yadi 1 sasti kalam ka muly 1.50 rupay avm 1 mahngi kalam ka muly 2 rupay hain to kitni mhngi kalme khridi gayi

Answer 1

Answer:

Costly pencils are 15 and cheap pencils are 20.

Solution:

let the x type of costly pencil has price 2 Rs

y type of cheap pencils has price 1.50 rs

ATQ

Total pencils are 35

So

$x + y = 35 .......eq1$
and all those pencils have cost 60,

So

$2x + 1.5y = 60......eq2$
Now solve these two equations

multiply eq1 by 2 and subtract both equations

$2x + 2y = 70 \\ 2x + 1.5y = 60 \\ - \: \: \: \: - \: \: \: \: \: \: \: \: \: \: - \\ - - - - - - - - - \\ 0.5y = 10 \\ \\ y = \frac{10}{0.5} \\ \\ y = \frac{10 \times 10}{5} \\ \\ y = 20$
So

$x + 20 = 35 \\ \\ x = 35 - 20 \\ \\ x = 15$
Hence costly pencils are 15 and cheap pencils are 20.


Hope it helps you.