Emma bought some gifts for her students at an average price of $10.70. If Emma decided to buy a pen which cost $15 for her father and a bag which cost $50 for her mother, the average price of the gifts would become $16.15. How many gifts did Emma buy for her students?
| |
Students |
Students and parents |
| Number |
1 u |
1 u + 2 |
| Value |
10.70 |
16.15 |
| Total Value |
10.70 u |
16.15 u + 32.30 |
Number of gifts that Emma bought for her students = 1 u
Amount that Emma spent on the gifts for her students
= 1 u x 10.70
= 10.70 u
Amount that $(Lizy) spent if she bought for her parents
= 15 + 50
= $65
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
= 16.15(1 u + 2)
= 16.15 u + 32.30
10.7 u + 65 = 16.15 u + 32.30
16.15 u - 10.7 u = 65 - 32.30
5.45 u = 32.70
1 u = 32.70 ÷ 5.45 = 6
Number of gifts that she bought for her students
= 1 u
= 6
Answer(s): 6
