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.
X is twenty
2x+6x+20=180
8x=160
X=20
Answer:
For #2: It's C. 17 nickels and 15 quarters.
Step-by-step explanation:
17*5= 85
15*25= 375
375+85= 460
add in the decimal:
17* 5 cents= $.85
15* 25 cents= $3.75
$3.75+ $.85= $4.60
Answer: the sand in the new terrarium is 2 inches deep.
Step-by-step explanation:
Zach has a terrarium with the dimensions of 20 by 8 and the terrarium was filled with 3 inches of sand. It means that the volume of sand that this terrarium contains is
20 × 8 × 3 = 480 inches³
Zach gets a new terrarium that is larger with the dimensions of 10 by 24. If Zach moved the existing sand in the new terrarium and the height of the sand is represented by h, then the volume of sand into he new terrarium is
10 × 24 × h = 240h
Since the volume of sand in both terrariums is equal, then
240h = 480
h = 480/240
h = 2 inches
With respect to the parent function,
y = 1/(x+5) +2
is translated 5 units left and 2 units up.