If $500 is put into a savings account at 9% interest compounded continuously, how much will it be worth at the end of 3 years? How many years will it take to double in value?

$654.98

Around 7.7 years

Step-by-step explanation:

Value = P × e^(rt)

= 500 × e^(0.09×3)

= 500 × e^(0.27)

= 654.9822254

Double: 500 × 2 = 1000

1000 = 500 × e^(0.09t)

e^(0.09t) = 2

Use ln both sides

0.09t × lne = ln2

t = ln2 ÷ 0.09

t = 7.70163543

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.