You mean, what is this number?
we can rephrase it like this: the sum of a number x and 8 is 15
which is:
x+8=15
we subtract 8 from both sides and we get
x=7
so the answer is 7.
The picture in the attached figure
we know that
perimeter of a rectangle=2*[base+height]
base=3y+1
height=2y+3
perimeter=90 units
so
90=2*[(3y+1)+(2y+3)]-----> 90=2*[5y+4]----> 10y+8=90----> y=8.2 units
base=3y+1-----> base=3*8.2+1-----> 25.6 units
height=2y+3----> height= 2*8.2+3---> 19.4 units
the answer is<span>
the length of side vy is (2y+3)-----> 19.4 units</span>
Note :- If sample size n > 30 OR Population standard deviation σ is given then We use Z test.
If sample size n < 30 AND Population standard deviation σ is unknown then we use t test.
In this question we are not given Population standard deviations σ1 and σ2.
Also n1 = 14 and n2 = 13 both sample sizes are LESS than 30.
Therefore we use t test.
Given :- Assume the population standard deviations are equal. ( σ1 = σ2)
then Degrees of freedom = n1 + n2 - 2 = 14 + 13 - 2 = 25.
(kindly find the image attached with this solution)
Answer :- Therefore 25 degrees of freedom are used to find the t critical value.
Answer:
A) College Student
Step-by-step explanation: