Answer:
12/30
Step-by-step explanation:
So we know that the denominator-numerator=18
And we also know that it's equal to 4/10 or 2/5.
Soooooooooooooo the most easiest is just to trial and error: 12/30
But I don't really know the more complex formula...
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
Since the price is increasing by percentage, rather than a constant rate, we will be using the exponential equation format, which is y=ab^x (a = initial value, b = growth/decay)
Since the value was $590 in the year 2000, 590 will be our a variable.
Since the value is *increasing* by 35%, add 1 and 0.35 (35% in decimal form) together to get 1.35. 1.35 is going to be your b variable.
Putting our equation together, our equation is f(x) = 590(1.35)^x
