Esther bought some gifts for her cousins at an average price of $11.70. If Esther decided to buy a pen which cost $14 for her father and a bag which cost $43 for her mother, the average price of the gifts would become $15.90. How many gifts did Esther buy for her cousins?
| |
Cousins |
Cousins and parents |
| Number |
1 u |
1 u + 2 |
| Value |
11.70 |
15.90 |
| Total Value |
11.70 u |
15.90 u + 31.80 |
Number of gifts that Esther bought for her cousins = 1 u
Amount that Esther spent on the gifts for her cousins
= 1 u x 11.70
= 11.70 u
Amount that $(Lizy) spent if she bought for her parents
= 14 + 43
= $57
Total number of items bought if she bought for her parents and her cousins
= 1 u + 1 + 1
= 1 u + 2
Total amount that she spent if she bought for her parents and her cousins
= 15.90(1 u + 2)
= 15.90 u + 31.80
11.7 u + 57 = 15.90 u + 31.80
15.90 u - 11.7 u = 57 - 31.80
4.2 u = 25.20
1 u = 25.20 ÷ 4.2 = 6
Number of gifts that she bought for her cousins
= 1 u
= 6
Answer(s): 6
