please help with these questions?

Question

a)-A population of Wombats is growing at a constant percent rate. If the population on January 1st is 1012 and a year later is 1080, what is its yearly percent growth rate to the nearest tenth of a percent?

b)- their growth rate is constant over time, what is their monthly growth rate to the nearest tenth of a percent? Assume a constant sized month. 

Answer 1

Hello, Maria,

I'm not certain I've taken the correct approach, so please look at my numbers with suspicion.

For the monthly rate, we see that the growth over 12 months was 68 wombats. That would be 68/12, or 5.67 wombats per month. 5.67/1012 is a growth rate of 0.56% per month. They ask for the nearest tenth of a percent, so that would be 0.6%. That really isn't totally accurate, since it doesn't take into account the compounding effect, in that the number is slighly higher each month. If you are studing compounding, then this would need to be adjusted.

Fr the year, the growth is 68 wombats. That would be a growth rate of 68/1012, or 6.7%.

Bob