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 <u>sum of all observations divided by the number of observations</u>.
In this problem:
- In the first 5 observations, total of 21 out of 25 points, hence the mean for these observations is
. - In the next n observations, mean of 1.
Hence, the mean is:

We want the mean to be of 0.9, thus:





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 brainly.com/question/25323941
Since 4 = $3.88
Then 1 = 3.88/4
= $ 0.97
Answer:
see explanation
Step-by-step explanation:
Calculate the distance (d) using the distance formula
d = √ (x₂ - x₁ )² + (y₂ - y₁ )²
with (x₁, y₁ ) = (6, 5) and (x₂, y₂ ) = (- 3, 1)
d = 
= 
= 
=
≈ 9.85 ( to 2 dec. places )
SOH CAH TOA
Sine is opposite over hypotenuse so you're answer is C.
:)))