Answer:
x = -2
y = 6
Step-by-step explanation:
i multiplied the 1st equation by 3 and the 2nd by 5 to get the y-terms to zero out
12x + 15y = 66
+ <u>35x - 15y = -160</u>
47x = -94
x = -94/47
x = -2
substitute -2 for 'x' to solve for 'y':
4(-2) + 5y = 22
-8 + 5y = 22
5y = 30
y = 6
Answer:
He must survey 123 adults.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the z-score that has a p-value of
.
The margin of error is:

Assume that a recent survey suggests that about 87% of adults have heard of the brand.
This means that 
90% confidence level
So
, z is the value of Z that has a p-value of
, so
.
How many adults must he survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage?
This is n for which M = 0.05. So






Rounding up:
He must survey 123 adults.
Answer:
0.02116402116
Or otherwise written as- 0.211
Answer:
Therefore all numbers that end with five and are greater than five are composite numbers. The prime numbers between 2 and 100 are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89 and 97.
Step-by-step explanation: