Will bought some staplers at $3 each. He later sold them to his customers at $7 each. For customers who bought three staplers were given another stapler for free. The customers bought either one or three staplers. Will gave away 130 free staplers and collected a total of $1290 more than what he had paid for. How many customers bought just one stapler each?
|
Staplers sold |
Staplers given to customers who got 1 stapler each |
Staplers given to customers who got 4 staplers each |
Number |
1 u |
1 u - 520 |
520 |
Value |
$3 |
$7 |
$7 |
Total Value |
3 u |
7 u - $3640 |
$2730 |
Since 130 staplers were given free, there were 130 customers who bought three staplers each.
Number of staplers that each customer would get if they bought three staplers each and got 1 stapler free
= 3 + 1
= 4
Total number of staplers for customers who each bought three staplers
= 4 x 130
= 520
Number of staplers for customers who each bought 1 stapler = 1 u - 520
Total amount collected from customers who bought 1 stapler each
= 7 x (1 u - 520)
= 7 u - 3640
Total amount collected from customers who bought three staplers each
= 130 x 3 x 7
= $2730
Total amount collected from all the customers
= 7 u - 3640 + 2730
= 7 u - 910
Will collected a total of $1290 more than what he had paid for.
7 u - 910 = 3 u + 1290
7 u - 3 u = 1290 + 910
4 u = 2200
1 u = 2200 ÷ 4 = 550
Number of customers who bought just one stapler
= 1 u - 520
= 550 - 520
= 30
Answer(s): 30