Shannon bought some gifts for her siblings at an average price of $13.70. If Shannon decided to buy a pen which cost $13 for her father and a bag which cost $40 for her mother, the average price of the gifts would become $16.90. How many gifts did Shannon buy for her siblings?
| |
Siblings |
Siblings and parents |
| Number |
1 u |
1 u + 2 |
| Value |
13.70 |
16.90 |
| Total Value |
13.70 u |
16.90 u + 33.80 |
Number of gifts that Shannon bought for her siblings = 1 u
Amount that Shannon spent on the gifts for her siblings
= 1 u x 13.70
= 13.70 u
Amount that $(Lizy) spent if she bought for her parents
= 13 + 40
= $53
Total number of items bought if she bought for her parents and her siblings
= 1 u + 1 + 1
= 1 u + 2
Total amount that she spent if she bought for her parents and her siblings
= 16.90(1 u + 2)
= 16.90 u + 33.80
13.7 u + 53 = 16.90 u + 33.80
16.90 u - 13.7 u = 53 - 33.80
3.2 u = 19.20
1 u = 19.20 ÷ 3.2 = 6
Number of gifts that she bought for her siblings
= 1 u
= 6
Answer(s): 6
