It is a function because each x value only has one y value
Due to the fact that mode means most present number your answer would be mode or 100 dollars
Answer: 1) The best estimate for the average cost of tuition at a 4-year institution starting in 2020 =$ 31524.31
2) The slope of regression line b=937.97 represents the rate of change of average annual cost of tuition at 4-year institutions (y) from 2003 to 2010(x). Here,average annual cost of tuition at 4-year institutions is dependent on school years .
Step-by-step explanation:
1) For the given situation we need to find linear regression equation Y=a+bX for the given situation.
Let x be the number of years starting with 2003 to 2010.
i.e. n=8
and y be the average annual cost of tuition at 4-year institutions from 2003 to 2010.
With reference to table we get
By using above values find a and b for Y=a+bX, where b is the slope of regression line.
and
∴ To find average cost of tuition at a 4-year institution starting in 2020.(as n becomes 18 for year 2020 if starts from 2003 ⇒X=18)
So, Y= 14640.85 + 937.97×18 = 31524.31
∴The best estimate for the average cost of tuition at a 4-year institution starting in 2020 = $31524.31