Answer:
2240
Step-by-step explanation:
7% of 8000 is 560, and 28% of 8000 is 2240. 560 x 4 is also 2240.
<span>There are several ways to do this problem. One of them is to realize that there's only 14 possible calendars for any year (a year may start on any of 7 days, and a year may be either a leap year, or a non-leap year. So 7*2 = 14 possible calendars for any year). And since there's only 14 different possibilities, it's quite easy to perform an exhaustive search to prove that any year has between 1 and 3 Friday the 13ths.
Let's first deal with non-leap years. Initially, I'll determine what day of the week the 13th falls for each month for a year that starts on Sunday.
Jan - Friday
Feb - Monday
Mar - Monday
Apr - Thursday
May - Saturday
Jun - Tuesday
Jul - Thursday
Aug - Sunday
Sep - Wednesday
Oct - Friday
Nov - Monday
Dec - Wednesday
Now let's count how many times for each weekday, the 13th falls there.
Sunday - 1
Monday - 3
Tuesday - 1
Wednesday - 2
Thursday - 2
Friday - 2
Saturday - 1
The key thing to notice is that there is that the number of times the 13th falls upon a weekday is always in the range of 1 to 3 days. And if the non-leap year were to start on any other day of the week, the numbers would simply rotate to the next days. The above list is generated for a year where January 1st falls on a Sunday. If instead it were to fall on a Monday, then the value above for Sunday would be the value for Monday. The value above for Monday would be the value for Tuesday, etc.
So we've handled all possible non-leap years. Let's do that again for a leap year starting on a Sunday. We get:
Jan - Friday
Feb - Monday
Mar - Tuesday
Apr - Friday
May - Sunday
Jun - Wednesday
Jul - Friday
Aug - Monday
Sep - Thursday
Oct - Saturday
Nov - Tuesday
Dec - Thursday
And the weekday totals are:
Sunday - 1
Monday - 2
Tuesday - 2
Wednesday - 1
Thursday - 2
Friday - 3
Saturday - 1
And once again, for every weekday, the total is between 1 and 3. And the same argument applies for every leap year.
And since we've covered both leap and non-leap years. Then we've demonstrated that for every possible year, Friday the 13th will happen at least once, and no more than 3 times.</span>
Answer: n = 267
Step-by-step explanation: <u>Margin</u> <u>of</u> <u>Error</u> shows the percentage that will differ the result you get from the real population value or, in other words, is the range of values in a confidence interval.
It can be calculated as
margin of error =
in which
z is z-score related to the confidence interval, which is this case is 1.96;
s is standard deviation;
n is the number in a sample;
So, the number of mice must be:
margin of error =
n = 267
<u>For the margin of error with 95% confidence interval be 0.6, it is needed </u><u>267 mice</u><u>.</u>
Answer:
x = 25.
Step-by-step explanation:
Since the side of the triangle that is labeled as 60 units bisects the right angle of the largest triangle, we can say that the smallest triangle, medium triangle, and largest triangle are all similar.
Since the smaller length of the middle triangle corresponds to x, and the longer length of the middle triangle (144) corresponds to the longer length of the smaller triangle (60), we can set up a proportion!
144 * x = 60 * 60
144x = 3600
2x = 50
x = 25
Hope this helps!
Answer: was up g, but i dont know i bet there are better people that can answer this qyestion
Step-by-step explanation:
bye call me syke JK