Problema Solution
Suppose you own a card shop. You buy one line of cards at a rate of 4 cards for $5. You plan to sell thecards at a rate of 3 for $5. How many cards must you sell to make a profit of $100?
Answer provided by our tutors
Let
x = the number of cards i must sell to make $100 profit
If I buy 4 cards for 5$ then the buy price of 1 card is $5/4.
If I sell 3 cards for 5$ then the sell price of 1 card is $5/3.
The profit that i will make from selling one car is = sell price - buy price.
If I buy x cards the total profit will be
x*(5/3 - 5/4) = 100
x = 240 cards
I must sell 240 cards.