Diana bought some gifts for her students at an average price of $13.40. If Diana decided to buy a pen which cost $18 for her father and a bag which cost $44 for her mother, the average price of the gifts would become $16.60. How many gifts did Diana buy for her students?
| |
Students |
Students and parents |
| Number |
1 u |
1 u + 2 |
| Value |
13.40 |
16.60 |
| Total Value |
13.40 u |
16.60 u + 33.20 |
Number of gifts that Diana bought for her students = 1 u
Amount that Diana spent on the gifts for her students
= 1 u x 13.40
= 13.40 u
Amount that $(Lizy) spent if she bought for her parents
= 18 + 44
= $62
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
= 16.60(1 u + 2)
= 16.60 u + 33.20
13.4 u + 62 = 16.60 u + 33.20
16.60 u - 13.4 u = 62 - 33.20
3.2 u = 28.80
1 u = 28.80 ÷ 3.2 = 9
Number of gifts that she bought for her students
= 1 u
= 9
Answer(s): 9
