5x-9=18
Add 9 to both sides
5x-9+9= 18+9
5x= 27
Now divide both sides by 5 to solve for x
5x/5= 27 /5
x=27/5 or 5.4
Answer:

Step-by-step explanation:
When finding the average of a set of numbers, we
- A) Add up all the numbers
- B) Divide that sum by the total number of numbers in the data set
Let's represent this with a formula, s being the sum of all numbers, n being the total number of numbers.

Since we <u>already know the sum</u> and we <u>know how many numbers there are</u> (8), we can substitute inside our expression
to find the average.
Therefore, the average of all these numbers is 11.25.
Hope this helped!
Answer:
Hardy has 470 more tennis balls than Kerns.
Step-by-step explanation:
Given that:
Total number of tennis balls = 940
Let,
x represents the number of tennis balls Hardy has.
y represents the number of tennis balls Kerns has.
According to given statement,
x+y=940 Eqn 1
x = 3y Eqn 2
Putting x = 3y in Eqn 1
3y+y=940
4y=940
Dividing both sides by 4

Putting y=235 in Eqn 2
x = 3(235)
x = 705
Difference = Hardy's tennis balls - Kerns' tennis balls
Difference = 705 - 235 = 470
Hence,
Hardy has 470 more tennis balls than Kerns.
Answer:
6.6
Step-by-step explanation:
Answer:
78%
Step-by-step explanation:
70 = 0.50 (62) + 0.50 (x)
70 = 31 + 0.5x
39 = 0.5x
x = 78
You must get at least a 78% on the test to have at least 70% in the class.