Answer: (0.00027144, 0.00036176)
Step-by-step explanation:
The sample proportion of cell phone users who develop cancer of the brain or nervous system =
Sample size : 420027
Confidence interval for p: , where = sample proportion , n= sample size , z* = crirical z value.
For 90% confidence interval , z*= 1.645
Required confidence interval:
A 90% confidence interval estimate of the percentage of cell phone users who develop cancer of the brain or nervous system = (0.00027144, 0.00036176)
We have an equation: ?/100= 50/125
Cross multiply:
125*?= 50*100
⇒ ?= 50*100/125= 40
40% of 125 is 50~
Answer:
[(2 + √3)/4] = 0.9330127
Step-by-step explanation:
We know that
cos (pi/12) ^ 2 =
cos (pi/12)* cos (pi/12) =
[(√6 + √2)/4]*[(√6 + √2)/4] =
(0.9659)*(0.9659) = 0.9330127
[(2 + √3)/4] = 0.9330127
8x-6>-9x+5x
8x-6>-4x
8x+4x>6
X>1/2
1.12 for decimal and for fraction 1 3/25