A financial analyst wanted to estimate the mean annual return on mutual funds. A random sample of 60 funds' returns shows an average rate of 12%. If the population standard deviation is assumed to be 4%, the 95% confidence interval estimate for the annual return on all mutual funds is
A. 0.037773 to 0.202227
B. 3.7773% to 20.2227%
C. 59.98786% to 61.01214%
D. 51.7773% to 68.2227%
E. 10.988% to 13.012%
Answer: E. 10.988% to 13.012%
Step-by-step explanation:
Given;
Mean x= 12%
Standard deviation r = 4%
Number of samples tested n = 60
Confidence interval is 95%
Z' = t(0.025)= 1.96
Confidence interval = x +/- Z'(r/√n)
= 12% +/- 1.96(4%/√60)
= 12% +/- 0.01214%
Confidence interval= (10.988% to 13.012%)
Answer:
-0.25
Step-by-step explanation:
→ Find fg(x)
2 ( x + 1 )² = 2x² + 4x + 2
→ Find gf(x)
2x² + 1
→ Equate them
2x² + 1 = 2x² + 4x+ 2
→ Move everything to the right hand side
0 = 4x + 1
→ Solve
x = -0.25
A c and d are the answers
To solve this problem you must apply the proccedure shown below:
1. Let's round the value to the nearest hundredth. As you can see, the digit 8 is in the thousandths place and is greater than 5, therefore, you must round up to 0.038.
2. Now express the value as a single digit times a power of 10, as following:
x
Therefore, the answer is:
x