False. It’s should be 3/4
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:
a = - 6
Step-by-step explanation:
Given
f(x) = 3x + 5 , then
f(a) = 3a + 5 and f(a) = - 13 , then equating the right sides
3a + 5 = - 13 ( subtract 5 from both sides )
3a = - 18 ( divide both sides by 3 )
a = - 6
a very fast way to do it:
Trivially 8.8*5>10, so the power of 10 is 6+2+1 = 9.
Therefore, the answer is 
the value of x is 8 cm.
<u>Step-by-step explanation:</u>
Correct Question : In the diagram, the radius of the outer circle is 2x cm and the radius of the inside circle is 6 cm. The area of the shaded region is 220π cm2. What is the value of x? Enter your answer in the box.
We have ,
the area of a circle = πr²
the outer circle area = 
the inside circle area = 
According to Question,
the outer circle area - the inside circle area = he shaded region
⇒ 
⇒ 
⇒ 
⇒
Therefore , the value of x is 8 cm.