Winnie bought some presents for her relatives at an average price of $10.20. If Winnie decided to buy a pen which cost $14 for her father and a bag which cost $48 for her mother, the average price of the presents would become $15.40. How many presents did Winnie buy for her relatives?
| |
Relatives |
Relatives and parents |
| Number |
1 u |
1 u + 2 |
| Value |
10.20 |
15.40 |
| Total Value |
10.20 u |
15.40 u + 30.80 |
Number of presents that Winnie bought for her relatives = 1 u
Amount that Winnie spent on the presents for her relatives
= 1 u x 10.20
= 10.20 u
Amount that $(Lizy) spent if she bought for her parents
= 14 + 48
= $62
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
= 15.40(1 u + 2)
= 15.40 u + 30.80
10.2 u + 62 = 15.40 u + 30.80
15.40 u - 10.2 u = 62 - 30.80
5.2 u = 31.20
1 u = 31.20 ÷ 5.2 = 6
Number of presents that she bought for her relatives
= 1 u
= 6
Answer(s): 6
