the very rigorous medical program at a local university has a 10% drop-out rate for each year. If the school admits 1,000 freshmen, how many diplomas will need to be ordered 4 years later?

Question

anonymous · Answer

FIRST YEAR: 1000 x 0.9 = 900
SECOND YEAR: 900 x 0.9 = 810

And so on. See the pattern?

anonymous · Answer

I will add that the 0.9 is taken from the 90% of students who stick with medicine each year. If you don't feel comfortable doing it like this, you can find the 10% of students and just subtract that from the total each year.

anonymous · Answer

but 630 isn't one of the answers

anonymous · Answer

which 630 is what i got doing it the way you did

parthkohli · Answer

$$\Large 1000 * (0.9)^{4}$$
Solve this :)

anonymous · Answer

FIRST YEAR: 1000 x 0.9 = 900
SECOND YEAR: 900 x 0.9 = 810
THIRD YEAR: 810 x 0.9 = 729
FOURTH YEAR: 729 x 0.9 = 656.1

It helps to walk yourself through each step. ParthKohli gave you the equation, but it's best to see how it's broken down.

anonymous · Answer

thanks all for the help :)

parthkohli · Answer

Exactly, compound interest is also like this. :) You use the exponents.