Tammy bought some gifts for her relatives at an average price of $11.80. If Tammy decided to buy a pen which cost $12 for her father and a bag which cost $50 for her mother, the average price of the gifts would become $14.20. How many gifts did Tammy buy for her relatives?
| |
Relatives |
Relatives and parents |
| Number |
1 u |
1 u + 2 |
| Value |
11.80 |
14.20 |
| Total Value |
11.80 u |
14.20 u + 28.40 |
Number of gifts that Tammy bought for her relatives = 1 u
Amount that Tammy spent on the gifts for her relatives
= 1 u x 11.80
= 11.80 u
Amount that $(Lizy) spent if she bought for her parents
= 12 + 50
= $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
= 14.20(1 u + 2)
= 14.20 u + 28.40
11.8 u + 62 = 14.20 u + 28.40
14.20 u - 11.8 u = 62 - 28.40
2.4 u = 33.60
1 u = 33.60 ÷ 2.4 = 14
Number of gifts that she bought for her relatives
= 1 u
= 14
Answer(s): 14
