Answer: 1692
Step-by-step explanation:
Formula to find the sample size :

Given : Confidence level : 
⇒ significance level =
z-value for 90% confidence interval (using z-table)=
Prior estimate of the population proportion (p) of customers who keep up with regular vehicle maintenance is unknown.
Let we take p= 0.5
Margin of error : E= 2%=0.02
Now, the required sample size will be :

Simplify , we get

Hence, the required sample size = 1692
Answer:
Hi! The correct answer is x=b^2/c, c=b^2/x
Step-by-step explanation:
<em><u>~Solve the rational equation by combining expressions and isolating the variable c and b~ </u></em>
9xh = total cost of the hat
9 per hat - 4 = $5 each scarf
h = hat
s = scarf
(9xh) + (5x s)
(9x7) + (5x9) = 108
Answer: The height of the flagpole is 12 feet.
Step-by-step explanation:
Let the height of the flagpole be 'H'.
So, from the figure, we can conclude that, the height and shadow of the flagpole is in proportion to the height and shadow of the stick.
Given:
Height of stick is,
Shadow of the stick is,
Shadow of the flagpole is,
Now, as these are in proportion, we have
Plug in the given values and solve for 'H'. This gives,
Hence, the height of the flagpole is 12 feet.
Answer:
50 pens
Step-by-step explanation:
x= 25 percent of 200
25/100 times X/200
Cross multiply them and you get
100x=5000
X=5000/100
X=50
25 percent of 200 is 50.
Which means they have away 50 pens