Expert: Steve Holleran - 4/13/2008

Question
Dear sir,

I am very week in math. I have got few problems in mathmatics. I will be very grateful to you if you could solve the problems bellow and explain the steps. Thank you very much.

I find these questions very difficult.

Question 1 : When the price of a product was reduced by 20 %, the sales in euros rose by 4 %. Find the
percent increase in the number of products sold ?



Question 2:

After a rise in the price of petrol, the driven mileage dropped by 6.7%. However, the fuel costs increased by 4.5%. By what percent did the petrol price rise?



Question 3:

A retailer buys a batch of 50 items of a product for 10 000 €. He then sets a price so that the
selling price is 80 % higher than the buying price. When there is 40 % left of the batch, the
retailer lowers the price and manages to sell off the rest for a reduced selling price of
171 €/item.
a) Calculate the discount percentage relative to the initial selling price.
b) Calculate the profit percentage for the whole batch.
Give your answers with an accuracy of one decimal.

Answer
Hi Gufran,

I'm having difficulty understanding these questions.

1.  If the sales rose 4%, then that's the percent increase in the # of products sold.  I don't see what the price reduction has to do with it.

2.  Here again, if the fuel costs increased by 4.5%, that's the % increase in the petrol price.  

Are you sure there's not more to these problems?

3.  I don't understand what the first part is referring to: "discount percentage relative to the  initial selling price"?

For the profit percentage, the initial cost is 10,000€,

that's 200€ each , so an 80% increase would be 360€ each.

He sells 40%, or 30 items at 360€ = 10,800€
He sells 60%, or 20 items at 171€ =  3,420€  total = 14,220€

So the profit percent would be 14,220 - 10,000 = 4220/10,000=0.422

or 42.2%

Sorry that's the best I can do with what's here.

Steve