The given regression shows the relationship between the numbers of car washed(x) and the amount earned for charity(y).
y = 10x + 20
We are to calculate the amount of charity if 50 cars are washed. Number of cars are represented by x, so by substituting x = 50 in above equation we can find the amount of charity that is earned by washing 50 cars.
y = 10(50) + 20 = $ 520
Thus, the charity can earn $520 if 50 cars come in for a wash.
Given:
The frequency distribution table.
To find:
The mean average score on a test.
Solution:
The frequency distribution table is

x a xa
y b yb
z c zc
Sum a+b+c xa+yb+zc
Now, the mean average score on the test is


Therefore, the mean average score on the test is
.
Answer:
$12.49
Step-by-step explanation:
9.99 divided by .8
... <span>exactly one output for each input
This is an important concept; be certain that you understand it.
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