Is it number 21 you need help with?
Answer:
12
Step-by-step explanation:
using pythagoras theorem
here 15 is hypotenuse since it is opposite 0f 90 degree
9 and x are the other smaller sides of a triangle
according to pythagoras thorem the sum of square of two smaller sides of a triangle is equal to the square of hypotenuse. So,
9^2 + x^2 = 15^2
81 + x^2 = 225
x^2 = 225 - 81
x^2 = 144
x = 
x = 12
Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.28.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Answer:
b,b.a
Step-by-step explanation:
[(8 - 2 * 29)]/3
Let's solve inside the brackets first.
According to PEMDAS, multiplication gets solved before subtraction so multiply 2 * 29 in the parentheses.
[(8 - 58)]/3
Subtract 58 from 8 in the parentheses.
(-50)/3
Divide -50 by 3.
-16.667 or -16 2/3 is your answer.