amount changed divided by original amount

Question

Marla makes beaded purses and sells them to Bangles 'n' Beads for $7 each.Bangles 'n' Beads make a 28% profit on each purse. Find the retail price of the purses.

Answer 1

If Marla sells the purses to Bangles n Beads for $7 and the store then marks them up in order to make a 28% profit, you need to figure out ho much they've marked them up.

 

So first you need to figure out what 28% of $7 is. That's 7 * .28 = $1.96

 

Now add this to the original $7 that the store paid to Marla to get the retail price of the purses. 7 + 1.96 = $8.96

Answer 2

Grace, this isn't as bad as it looks.

 

We know that the $7 includes a 28% profit.  

 

Let's say we bought something at Target that costs $5 but there is an 8% sales tax.  We can multiply 5(.08) = 40 cents and add that to $5 to get $5.40.

 

This means that we have $5 + $5(.08) = $5 + $.40 = $5.40.  

 

Remember that if we have 5(2) + 3(2), we can combine those into 8(2).  We can do the same with our original amount and tax.

 

$5(1.08) = $5.40

 

Now, we see again that the $7 includes a 28% profit.  If r = the retail price, then r(1.28) = $7.

 

r = $7/1.28 = $5.47.

 

Let's check.  28% of $5.47 = .28($5.47) = $1.53.  $5.47 + $1.53 = $7.  Check!

 

Doing it the other way you mentioned, if we let r = the retail price, then the difference is 7-r. We'd then have to divide that by the original price, which is the retail price, so we'd have (7 - r)/r = .28.

 

$7 - r = .28r

     $7 = 1.28r

       r = $5.47

 

Either way works.  Hope this helps!