Answer: 37
Step-by-step explanation:
Given : Significance level : 
Critical value : 
margin of error : E= 1 mile per gallon
Population standard deviation:
miles per gallon.
We know that when the population standard deviation is known then the formula to find the sample size is given by :

[Round to the next whole number.]
Hence, the required number of automobiles should be used in the test = 37
Answer:
41 years old.
Step-by-step explanation:
Let x represent age of younger child.
We have been given that a mother has two children whose ages differ by 5 years. So the age of older child would be
.
The sum of the squares of their ages is 97. We can represent this information in an equation as:

Let us solve for x.



Divide both sides by 2:






Since age cannot be negative, therefore, age of younger child is 4 years.
Age of older child would be 
Therefore, the age of older child would be 9 years.
We have been given that the square of the mother's age can be found by writing the squares of the children's ages one after the other as a four-digit number.
Square of 4: 
Square of 9:
.
Square of mother's age: 
To find mother's age, we need to take positive square root of 1681 as:

Therefore, the mother is 41 years old.
Answer is B. 4,096
I encountered this problem before. This is a trick question.
84 is not really the number 84. It is 8 raised to the 4th power.
So 8⁴ is equal to 4,096.
8 x 8 x 8 x 8 = 4,096
8 x 8 = 64
64 x 8 = 512
512 x 8 = 4,096
Answer:
3 inches apart
Step-by-step explanation:
1/2 yard is 1ft. 6in. in decimal that is 1.5 ft
1.5 ÷6 = 0.25ft
0.25ft is 3 inches so the answer is three inches apart
Answer:
C = pi * d = 2 * pi *r
Step-by-step explanation:
The circumference of a circle is the distance around the circle. It can be found by multiplying the diameter times pi.
C = pi * d
We can replace the diameter with twice the radius
C = pi * 2 * r = 2 * pi *r