Question

In the function for North Dakota, which of the following is the best interpretation of the number 149.5 in this context?A.) For the year 1965, the model predicts 149.5 thousand homes in North Dakota had access to a telephone.B.) For the year 2000, the model predicts 149.5 thousand homes in North Dakota had access to a telephone.C.) Between 1965 and 2000, the predicted number of homes with access to a telephone in North Dakota increased by a total of 149.5 thousand.D.) Between 1965 and 2000, the predicted number of homes with access to a telephone in North Dakota increased by 149.5 thousand each year.

Answer 1

Ok here we have two examples of linear functions. A linear function consist of a variable (in this case x which represents years) and two parameters: the slope (in this case 2.5 which represents how much D(x) increses when x increases) and the intercept (149.5 which represents the inical value of D(x) when x=0). D represents the number of houses with access to a telephone.

Let's check which of the items is correct:

In item A the speak about the number of houses with access to telephone (D) in 1965. Since x represents the years past after 1965 then if the year is 1965 then x=0.

And D=2.5*0+149.5=149.5. So there were 149.5 thousand homes with access to telephone in 1965 and this item is correct. So the answer is A.