Question

I need help with exponential regression...I have E(x)=164.96(1.03)^x for equation for high school graduates...need to find the first year of the decade in which number of graduates will reach 5 million

Answer 1

E a function of x, E is what and x is what? im guessing E is graduates and x is year?

Answer 2

yes I used cal to get a b and r

Answer 3

plug 5mill into E(x) and solve for x

Answer 4

yes got that but do I ln or log...can't remember

Answer 5

years are in decades and graduates are in 1000s so would I divide 5 mil by 100

Answer 6

do log base 1.03
there is probably a key on your calculator

Answer 7

is that ln

Answer 8

actually im sorry you are right take the natural log of both sides. and the exponent of x will come out as a multiple of ln(1.03)
so
\[\ln(1.03^x) = xln(1.03)\]
ln(1.03) is just a constant so you can divide by it on both sides

Answer 9

thank you for the confirmation

Answer 10

yeahp

Answer 11

one more thing I have year 2050 from the linear function and year 2070 from the exponential...which one seems more reasonable?

Answer 12

based on the values of correlation factor r the linear function would be but if you're looking at 5 million wouldn't it take less years to get there Exponentially versus linearly

Answer 13

im not sure from what was given i only know of E(x) and x,

Answer 14

L(x)=33.79x-135.77

Answer 15

used 5000 instead of 5 mil bc grads in 1000s is that right?

Answer 16

yeah

Answer 17

yeah to which question, lol?

Answer 18

lol just agreeing with the thing you said about linear versus exponential growth it would have to be 2050. but i would look into that more as to how to get to that answer

Answer 19

ok thanks!