Question

Not sure how to go about this derivative word problem.

Question:
https://mail-attachment.googleusercontent.com/attachment/u/0/?ui=2&ik=0f0df0826d&view=att&th=138648d3c3fa1da4&attid=0.1&disp=inline&realattid=1406891960424097157-1&safe=1&zw&saduie=AG9B_P_YPn2Qu4t_BhOXpAPFHAJc&sadet=1341716824152&sads=e6pR-NjdafdwDRCb4kPpWUlP3Ms

Graph:
https://mail-attachment.googleusercontent.com/attachment/u/0/?ui=2&ik=0f0df0826d&view=att&th=138648d3c3fa1da4&attid=0.2&disp=inline&realattid=1406891960424097157-2&safe=1&zw&saduie=AG9B_P_YPn2Qu4t_BhOXpAPFHAJc&sadet=1341716904391&sads=5T4T7drsGR_qlRDRuuwOkD

Answer 1

For A I got the avg rate as 22,326 people / year.
Wasn't sure how to do B or C.

Answer 2

We can't read the mail

Answer 3

Ok I'll attach them here hold on

Answer 4

First picture are the questions, second one is the graph and data table

Answer 5

i can't read the graph, but average rate of growth is the same as the slope of the line

Answer 6

population in 1980 - population in 1970 divided by 10

Answer 7

yeah I got 22,326 people/year

Answer 8

But how do I calculate instantaneous rate, at 1975?

Answer 9

guess

Answer 10

don't think ,you can actually "calculate" the instantaneous rate cause they don't give the function.
the secant line that represents the average rate between 1970 and 1980 is pretty close to the slope of the tangent line at 1975, t=25.

Answer 11

put a ruler down tangent to the curve at the point (1975,whatever) then guess as to what the slope of the ruler is

Answer 12

if the slope of the secant line between t=20 and t=30 is parallel or pretty close to parallel to the tangent line at t=25, then the average rate of change is a good estimate for the instantaneous rate of change.

Answer 13

after you put your ruler down, don't look near the point because that will confuse you
look to some other part of the ruler and compute (estimate) the slope

Answer 14

how could I estimate the rate at 2000?