A video sharing website starts with 20,000 members. Each year it loses 25% of the members, but adds 10,000 new members after the reduction. Write a recursive rule to find the number of members for any year.

Question

anonymous · Answer

@domebotnos @animal_lover36 @Gokuporter @TheGaMer007

thegamer007 · Answer

options?

perl · Answer

you can approach this as a recursive sequence

anonymous · Answer

attachment

perl · Answer

$$
t = 0 \
f(0) = 20000\
$$
$$t= 1 \
f(1) = .75 * 20,000 + 10,000 = .75 * f(0) + 10,000\

$$

anonymous · Answer

Thats not one of the options

anonymous · Answer

the answers are in the attachment but i can't figure out the right one

jtvatsim · Answer

How about answering an easier question first. Can you figure out how many members there will be in the second year based on the information?

anonymous · Answer

idk but for the problem is the answer B?

jtvatsim · Answer

Based on the question... I don't think so. B has a1 = 10,000 and a1 stands for the number of members in the first year. But we know that the number of members in the first year is 20,000 from the question.

anonymous · Answer

oh okay, so then that would mean that its A

jtvatsim · Answer

That is much better since a1 = 20,000... did you pick A because 25% = 0.25 ?

anonymous · Answer

yes

anonymous · Answer

so is that correct?

jtvatsim · Answer

Well, be careful. :) We lose 25% each year... but that leaves us with 75%... tricky

anonymous · Answer

huh so then it wouldn't be A

jtvatsim · Answer

Nope, there is another choice that is even better.

jtvatsim · Answer

You are getting closer.

anonymous · Answer

C?

jtvatsim · Answer

Looks good to me. a1 = 20,000 as needed, we have 0.75 = 75% and we are adding 10,000 each year. Seems to fit the bill perfectly.

anonymous · Answer

Thanks so much!!

jtvatsim · Answer

No worries good luck!