Here is the set up:
Let x and y be the two numbers with x the smaller and y the larger number.
x + y = 66
2x = y + 15
We have two equations in two unknowns.
Take it from here.
Im not entirely sure but i thinks its c
We need to find out how many adults must the brand manager survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage.
From the given data we know that our confidence level is 90%. From Standard Normal Table we know that the critical level at 90% confidence level is 1.645. In other words,
.
We also know that E=5% or E=0.05
Also, since,
is not given, we will assume that
=0.5. This is because, the formula that we use will have
in the expression and that will be maximum only when
=0.5. (For any other value of
, we will get a value less than 0.25. For example if,
is 0.4, then
and thus,
.).
We will now use the formula

We will now substitute all the data that we have and we will get



which can approximated to n=271.
So, the brand manager needs a sample size of 271
Answer:
25%.
Step-by-step explanation:
Let E be the event that the dart lands inside the triangle.
We have been given that a rectangular board has an area of 648 square centimeters. The triangular part of the board has an area of 162 square centimeters.
We know that probability of an event represents the chance that an event will happen.




Convert into percentage:

Therefore, the probability that dart lands inside the triangle is 25%.
The total change in her bank account would be $160,
if you multiply 8x$20 you get $160