Given:
Sample mean = 65.4
Standard deviation = 1.2
Sample size = 45
Confidence level = 99%
To find:
The confidence interval.
Solution:
The formula for confidence interval is

where,
is sample mean, z* is confidence value, s is standard deviation and n is sample size.
Confidence value or z-value at 99% = 2.58
Putting the given in the above formula, we get




Therefore, the correct option is D.
x + 4x = 40
5x = 40
x = 8
Mrs. Viola has 8 and Mrs. Rullo has 4*8=32 pens.
9/2 + 5/2
11/2
1/5
Answer: 70/11 (<span>6.363636)</span>
340 you were right
Step-by-step explanation:
Answer:
x = -1/4
Step-by-step explanation:
3/x = -4 - 8
3/x = -12
x= -3/12
x= -1/4