The cost price of 12 pens and 6 pencils is Rs. 168. What will be the cost price of 18 pens and 9 pencils ?
Let cost price of 1 pen = $$Rs. x$$
and cost price of 1 pencil = $$Rs. y$$
Acc. to ques, => $$12x + 6y = 168$$
Dividing both sides by 6, we get :
=> $$2x + y = 28$$
Now, multiplying both sides by 9, => $$9 (2x + y) = 9 (28)$$
=> $$18x + 9y = 252$$
$$\therefore$$ Cost price of 18 pens and 9 pencils = Rs. 252
Create a FREE account and get: