Joelle bought some gifts for her relatives at an average price of $13.50. If Joelle decided to buy a pen which cost $13 for her father and a bag which cost $36 for her mother, the average price of the gifts would become $15.70. How many gifts did Joelle buy for her relatives?
|
Relatives |
Relatives and parents |
Number |
1 u |
1 u + 2 |
Value |
13.50 |
15.70 |
Total Value |
13.50 u |
15.70 u + 31.40 |
Number of gifts that Joelle bought for her relatives = 1 u
Amount that Joelle spent on the gifts for her relatives
= 1 u x 13.50
= 13.50 u
Amount that $(Lizy) spent if she bought for her parents
= 13 + 36
= $49
Total number of items bought if she bought for her parents and her relatives
= 1 u + 1 + 1
= 1 u + 2
Total amount that she spent if she bought for her parents and her relatives
= 15.70(1 u + 2)
= 15.70 u + 31.40
13.5 u + 49 = 15.70 u + 31.40
15.70 u - 13.5 u = 49 - 31.40
2.2 u = 17.60
1 u = 17.60 ÷ 2.2 = 8
Number of gifts that she bought for her relatives
= 1 u
= 8
Answer(s): 8