# Thread: Desparet for HELP! Calculate average stay!

1. ## Desparet for HELP! Calculate average stay!

Hi guys!

I've been trying to figure out this math problem forever! I was hoping you could help out? =)

Month 1
- 100 sign-ups

Month 2
- 100 sign-ups
- 80 left from month 1

Month 3
- 100 sign-ups
- 80 left from month 2
- 40 left from month 1

Month 4
- 100 sign-ups
- 80 left from month 3
- 40 left from month 2
- 2 left from month 1

Average stay?

Thanks,
magnus

2. Are these the right numbers, because if they are than that means that 122 left from month 1 but only 100 people were signed up

3. ## sorry - my bad

Sorry, but I think I was a bit unclear with what I meant. This is how it should look:

Month 1
100 new sign-ups

Month 2
100 new sign-ups
80 of the sign-ups from month 1 is still "in the game"

Month 3
100 new sign-ups
80 of the sign-ups from month 2 is still in the game
40 out of the sign-ups from month 1 is still "in the game"

Month 4
100 new sign-ups
80 of the sign-ups from month 3 is still in the game
40 of the sign-ups from month 2 is still in the game
2 of the sign-ups from month 1 is still in the game

What is the average stay?