Answer: 37
Step-by-step explanation:
As per given description in the question, we have
Population standard deviation : 
Critical value for 98% confidence interval = 
Margin of error : E= 1 mile per gallon
Formula we use to find the sample size :

i.e. 

Therefore , the number of automobiles should be used in the test =37
Answer:
x = 5
Step-by-step explanation:
To break this down, I'll start from the first thing the question gives you. Triangle ACB is congruent to triangle DCE. This means that the angles and the sides of each triangle is the same. Now this next part is important. The way in which the letters are ordered is corresponds to what angles are the same. Since the triangles are congruent, ∠A in ΔACB would correspond to ∠D in DCE. Another example: ∠C in ACB is congruent to ∠C in ΔDCE. So if ∠A is congruent, or the same as ∠D, this means ∠D is 50°. Now, we just solve for x:
∠D = 10x
50° = 10x
Divide each side by 10 to isolate x:
50/10 = 10x/10
x = 5
Answer:
c
Step-by-step explanation:
100+5 =105
105 per day
6(105)=6(100)+6(5)
They both have the same answer: 630 as the total cost.