Answer:
a) 25
b) 49
c) 97
Step-by-step explanation:
The sample size is calculated using the formula, n = 
Now,
for 95% confidence level value of z-factor = 1.96
Given:
Mean = $3.94
standard deviation = $0.25
thus,
a) for margin of error = $0.10
n = 
or
n = 
or
n = 4.9²
or
n = 24.01 ≈ 25 (Rounded off to next integer)
b) for margin of error = $0.07
n = 
or
n = 
or
n = 7²
or
n = 49
c) for margin of error = $0.05
n = 
or
n = 
or
n = 9.8²
or
n = 96.04 ≈ 97 (Rounded off to next integer)
Answer:
80%; 30%
Step-by-step explanation:
There is 5 blue marbles, 2 black marbles, and 3 red marbles. In other words, there is a total of 10 marbles.
There are only 2 black marbles and 8 marbles that are not black. Therefore, the probability of <em>not</em> drawing a black marble is 8/10 or 4/5 or 80%.
There are only 3 red marbles out of the 10 total marbles. Therefore, the probability of drawing a red marble is 3/10 or 30%.
Let x be the number, then 60 = 40% of x & x =60/40%=60/0.4=150
then the number of which 60 represent 40% of it is 150
2) Let x be the time needed to the 16 clerks to finish the job
In one day the 32 clerks complete a portion of 32/22 of the job
In one day the 16 clerks complete a portion of 16/x of the job
So in 1 day===> 32/22 =16/x ==> x=(22*16)/32 = 11 days
3u+ 9 is the right answer, since thier not like terms you can’t add them