Juelle had $25,000 to invest. She invested part of that amount at 3% interest and part at 5% interest for one year. The amount of interest she earned for both investments was $1100. How much was invested at each rate?

The first amount invested at 3%= x = $7500

The second amount Invested at 5% = y = $17500

Step-by-step explanation:

Juelle had $25,000 to invest.

She invested part of that amount at 3% interest and part at 5% interest for one year.

The amount of interest she earned for both investments was $1100.

The formula for Simple Interest =

Principal × Rate × Time

Let us represent

The first amount invested at 3%= x

The second amount Invested at 5% = y

x + y= $25,000 Equation 1

x = 25,000 - y

3% × x + 5% × y = $1100 Equation 2

0.03x + 0.05y = 1100 Equation 2

We substitute 25000 - y for x in Equation 2

0.03x + 0.05y = 1100

0.03(25000 - y) + 0.05y = 1100

750 - 0.03y + 0.05y = 1100

Collect like terms

- 0.03y + 0.05y = 1100 - 750

0.02y = 350

y = 350/0.02

y = 17500

Solving for x

x = 25,000 - y

x = 25000 - 17500

x = 7500

Therefore:

The first amount invested at 3%= x = $7500

The second amount Invested at 5% = y = $17500

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.