Lynn bought some presents for her students at an average price of $10.80. If Lynn decided to buy a pen which cost $14 for her father and a bag which cost $46 for her mother, the average price of the presents would become $17.20. How many presents did Lynn buy for her students?
| |
Students |
Students and parents |
| Number |
1 u |
1 u + 2 |
| Value |
10.80 |
17.20 |
| Total Value |
10.80 u |
17.20 u + 34.40 |
Number of presents that Lynn bought for her students = 1 u
Amount that Lynn spent on the presents for her students
= 1 u x 10.80
= 10.80 u
Amount that $(Lizy) spent if she bought for her parents
= 14 + 46
= $60
Total number of items bought if she bought for her parents and her students
= 1 u + 1 + 1
= 1 u + 2
Total amount that she spent if she bought for her parents and her students
= 17.20(1 u + 2)
= 17.20 u + 34.40
10.8 u + 60 = 17.20 u + 34.40
17.20 u - 10.8 u = 60 - 34.40
6.4 u = 25.60
1 u = 25.60 ÷ 6.4 = 4
Number of presents that she bought for her students
= 1 u
= 4
Answer(s): 4
