IDNLearn.com is the place where your questions are met with thoughtful and precise answers. Ask any question and receive comprehensive, well-informed responses from our dedicated team of experts.
Sagot :
Using the mean concept, it is found that we will need 15 more points to bring up his average up to 90%.
The mean of a data-set is the sum of all observations divided by the number of observations.
In this problem:
- In the first 5 observations, total of 21 out of 25 points, hence the mean for these observations is [tex]\frac{21}{25} = 0.84[/tex].
- In the next n observations, mean of 1.
Hence, the mean is:
[tex]M = \frac{0.84(5) + n}{5 + n} = \frac{4.2 + n}{5 + n}[/tex]
We want the mean to be of 0.9, thus:
[tex]M = 0.9[/tex]
[tex]\frac{4.2 + n}{5 + n} = 0.9[/tex]
[tex]4.2 + n = 0.9n + 4.5[/tex]
[tex]0.1n = 0.3[/tex]
[tex]n = \frac{0.3}{0.1}[/tex]
[tex]n = 3[/tex]
3 more testes are need, each worth 5 points, hence, 15 more points are needed to bring up his average up to 90%.
A similar problem is given at https://brainly.com/question/25323941
Thank you for using this platform to share and learn. Keep asking and answering. We appreciate every contribution you make. Thank you for trusting IDNLearn.com. We’re dedicated to providing accurate answers, so visit us again for more solutions.
