Answer:
Firstly, from the diagram we are given that the length of XB is congruent to BZ, and YC is congruent to CZ. Based on this information, we know that B is the midpoint of XZ, and C is the midpoint of YZ. This means that BC connects the midpoints of segments XZ and YZ. Now that we know this, we can use the Triangle Midsegment Theorem to calculate the length of BC. This theorem states that if a segment connects the midpoints of two sides of a triangle, then the segment is equal to one-half the length of the third side. In this scenario, the third side would be XY, which has a length of 12 units. Therefore, the length of BC = 1/2(XY), and we can substitute the value of XY and solve this equation:
BC = 1/2(XY)
BC = 1/2(12)
BC = 6
Step-by-step explanation:
Please support my answer.
Answer:
Use 49 ounces of the 14% allow and 41 ounces of the 23% alloy.
Step-by-step explanation:
Each ounce of the 14% copper contains 0.14 ounce of pure copper.
Each ounce of the 23% copper contains 0.23 ounce of pure copper.
Each ounce of the 18.1% copper contains 0.181 ounce of pure copper.
Use x ounces of the 14% and y ounces of the 23% to make 90 ounces of 18.1% alloy.
x+y = 90
y = 90-x
0.14x + 0.23y = 0.181·90
0.14x + 0.23(90-x) = 16.29
0.14x + 20.7 - 0.23x = 16.29
-0.09x + 20.7 = 16.29
4.41 = 0.09x
x = 49
y = 90-x = 41
Use 49 ounces of the 14% allow and 41 ounces of the 23% alloy.
Answer:
a. 1.44
Step-by-step explanation:
We are interested in determining whether or not the proportion of the population in favor of Candidate A is significantly more than 40%.
At the null hypothesis, it is tested if the proportion is of at most 40%, that is:

At the alternative hypothesis, it is tested if the proportion is of more than 40%, that is:

The test statistic is:
In which X is the sample mean,
is the value tested at the null hypothesis,
is the standard deviation and n is the size of the sample.
0.4 is tested at the null hypothesis:
This means that 
A random sample of 200 people was taken. 90 of the people in the sample favored Candidate A.
This means that:

Value of the test statistic:



Thus the correct answer is given by option a.
Answer:
15 miles
Step-by-step explanation:
If there are 2.5 inches and 1 inch is 6 miles, then just multiply 6 by 2.5 to get 15
6*2.5=15
Answer:
P(black) = 2/3
Step-by-step explanation:
We need to find the total number of marbles
2 red marbles+ 3 white marbles+ 10 black marbles = 15 marbles
To find the probability that Sam chose a black marble, we take the number of black marbles and divide by the total number of marbles
P(black) = black marbles/total marbles
= 10/15
Divide the top and bottom by 5
= 2/3