chocolateforlife
Answered

In march, a customer spent $8.55 at an office-supply store for some 12-packs of pens. At that time, the store was selling packages of one dozen pens for $1.35. Any customer who bought more than 4 packages, received a discount of $0.30 on the price of each package in excess of 4 packages. In september, the same customer went back to the store to buy the same number of pens. By then, the price per 12-pack of pens had been raised to $1.50 each, with the same discount for more than 4 packages. How much more did the customer have to pay in September than in March?



Answer :

kavikafaleumu
We can start by making an equation from the information given on the month of March to find how many packs he bought.
[tex]4(1.35)+x(1.05)=8.55[/tex] This equation shows that for the first 4 packs he bought, he payed $1.35. Then, consequently, for each pack after that, he payed $0.30 less, and we don't know how many more he bought, so we set it up as shown. Finally, we set it all equal to $8.55 since that's how much he payed that month. We get that x=3, meaning that he bought a total of 7 packs of pens that month.
Knowing this, we can now make an equation for the month of September.
[tex]4(1.50)+3(1.20)=x[/tex] This time, we know the entire left side, that he paid $1.50 for the first 4 packs and $0.30 less for the last 3. We get x=$9.60
Knowing this, we can subtract the amount he paid in September by the amount he paid in March to get the answer... $9.60-$8.55=$1.05

I hope this helped!