15 = rate * 40
rate = 15/40
rate = 0.375 * 100% = 37.5%
Answer:
I don't really understand the question
Step-by-step explanation:
I don't know the answer
The greatest possible number of club members is 7
<em><u>Solution:</u></em>
Given that, local readers’ club has a set of 49 hardback books and a set of 21 paperbacks
Each set can be divided equally among the club members
To find the greatest possible number of club members, we have to find the greatest common factor of 49 and 21
The greatest number that is a factor of two (or more) other numbers.
When we find all the factors of two or more numbers, and some factors are the same ("common"), then the largest of those common factors is the Greatest Common Factor.
<em><u>Greatest common factor of 49 and 21:</u></em>
The factors of 21 are: 1, 3, 7, 21
The factors of 49 are: 1, 7, 49
Then the greatest common factor is 7
Thus, the greatest possible number of club members is 7
Answer:
- digits used once: 12
- repeated digits: 128
Step-by-step explanation:
In order for a number to be divisible by 4, its last two digits must be divisible by 4. This will be the case if either of these conditions holds:
- the ones digit is an even multiple of 2, and the tens digit is even
- the ones digit is an odd multiple of 2, and the tens digit is odd.
We must count the ways these conditions can be met with the given digits.
__
Since we only have even numbers to work with, the ones digit must be an even multiple of 2: 4 or 8. (The tens digit cannot be odd.) The digits 4 and 8 comprise half of the available digits, so half of all possible numbers made from these digits will be divisible by 4.
<h3>digits used once</h3>
If the numbers must use each digit exactly once, there will be 4! = 24 of them. 24/2 = 12 of these 4-digit numbers will be divisible by 4.
<h3>repeated digits</h3>
Each of the four digits can have any of four values, so there will be 4^4 = 256 possible 4-digit numbers. Of these, 256/2 = 128 will be divisible by 4.
Answer:
The correct option is (b).
Step-by-step explanation:
The (1 - <em>α</em>)% confidence interval for population mean (<em>μ</em>) is:

The confidence interval for population mean can be computed using either the <em>z</em>-interval or <em>t</em>-interval.
The <em>t</em>-interval is used if the following conditions are satisfied:
- The population standard deviation is not known
- The sample size is large enough
- The population from which the sample is selected is normally distributed.
For computing a (1 - <em>α</em>)% confidence interval for population mean , it is necessary for the population to normally distributed if the sample selected is small, i.e.<em>n</em> < 30, because only then the sampling distribution of sample mean will be approximated by the normal distribution.
In this case the sample size is, <em>n</em> = 28 < 30.
Also it is provided that the systolic blood pressure is known to have a skewed distribution.
Since the sample is small and the population is not normally distributed, the sampling distribution of sample mean will not be approximated by the normal distribution.
Thus, no conclusion can be drawn from the 90% confidence interval for the mean systolic blood pressure.
The correct option is (b).