Answer:
The answers is
x=−1
Step-by-step explanation:
Can you give me Brainleist please :)
Answer: c. 3.01
Step-by-step explanation:
The test statistic for difference between two population mean (when population standard deviation is known) is given by :

, where
= Size of first sample
= Size of second sample
= Difference between two sample mean.
= standard deviation for population 1.
= standard deviation for population 2.
As per given , we have



Substitute these values in formula , we get




Hence, the value of the test statistic is <u>3.01</u>.
Hence, the correct option is c. 3.01 .
Answers:
Step-by-step explanation:
<em>We must simplify each option to see if they are equivalent to
.</em>
<em>Lets try A.</em>
can be simplified to
by dividing both the numerator and denominator by 3.
÷ 
A is correct!
<em>Lets try B</em>
simplifies to
. However, because this answer is not negative, it is not equivalent.
<em>Lets try C</em>
There is a negative in the numerator, making this fraction negative. So yes,
.
- Bonus Info: If there was a negative in both the numerator and denominator, the two negatives would cancel eachother out, making the fraction positive
C is correct!
<em>Lastly, Lets try D</em>
There is a negative in the denominator, so this fraction is negative.
can be simplified by dividing by 3 to
.
÷3 = 
D is correct!
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Answer: See explanation
Step-by-step explanation:
a. how old is Cheryl?
Cheryl's age = d + 5
b. how old is Brandon?
d + 5 + 2
= d + 7
c. what was the difference in their ages 5 years ago?
Cheryl age five years ago = d
Brandon's age five years ago = d + 2
Difference = d + 2 - d = 2 years
d. what is the sum of their ages now?
Cheryl's age = d + 5
Brandon age = d + 7
Sum = d + 5 + d + 7
= 2d + 12
e. what will the sum of their ages be two years from now?
Two years from now,
Cheryl's age = d + 5 + 2 = d + 7
Brandon age = d + 7 + 2 = d + 9
Sum = d + 7 + d + 9
= 2d + 16
f. what will the difference of their ages be two years from now
Two years from now,
Cheryl's age = d + 5 + 2 = d + 7
Brandon age = d + 7 + 2 = d + 9
Difference = Brandon age - Cheryl age
= (d + 9) - (d + 7)
= 2 years.