Answer:
609
Step-by-step explanation:
Standard deviation =
= $30
Margin of error = E = $2
Confidence level = 90%
Since the distribution is said to be normal, we will use z scores to solve this problem.
The z score for 90% confidence level = z = 1.645
Sample size= n = ?
The formula to calculate the margin of error is:

Using the values in above equation, we get:

This means, the minimum number of observations required is 609
Answer:
18 divided by 22 is around 82
60 divided by 70 is around 86
Step-by-step explanation:
So the social studies test she scored higher
<span>First, you need to find out how much will the candle cost per volume. If a candle with a volume of 80cm^3 costs $12, the price of the candle per cm^3 would be: $12/80cm^3= $0.15/cm^3
Then the price of a candle with </span>120 cm^3 volume would be:120cm^3* $0.15/cm^3= $18
Answer:
110 students walk or bike to school.
Step-by-step explanation:
48% of the 208 students walk, whereas 5% bike. Combining 48% and 5%, we get 53%.
53% of the total number, n, comes to 208 students.
This number is 0.53(208 students), or 110 students.
110 students walk or bike to school.
Answer:
The measure of arc BD is 147°
Step-by-step explanation:
we know that
If segment AB is perpendicular to segment CD
then
The measure of the inner angle CPA is a right angle (90 degrees)
Remember that
The measure of the inner angle is the semi-sum of the arcs comprising it and its opposite.
so
m∠CPA=(1/2)[arc AC+arc BD]
substitute the given values
90°=(1/2)[33°+arc BD]
180°=33°+arc BD
arc BD=180°-33°=147°