Answer:
1120 combinations of four teachers include exactly one of either Mrs. Vera or Mr. Jan.
Step-by-step explanation:
The order in which the teachers are chosen is not important, which means that the combinations formula is used to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.
In this question:
1 from a set of 2(Either Mrs. Vera or Mr. Jan).
3 from a set of 18 - 2 = 16. So

1120 combinations of four teachers include exactly one of either Mrs. Vera or Mr. Jan.
Answer:
13. 16+16-16+16x = 16+16x
Answer:
times it by 3 on both sides should get 180
Step-by-step explanation:
Answer:
3x+2y
Step-by-step explanation:
Find the rectangles attached
Area of a rectangle = Length * Width
A = A1+A2
given
A = 30cm²
A1 = 3 * x
A1 = 3x
A2 = 2*y
A2 = 2y
Substitute
30 = 3x+2y
Hence the required equation is 3x+2y = 30
Answer:
There is significant evidence that treatment will create effect on the subject. Hence We reject H0
Step-by-step explanation:
H0 : μ = 37
H1 : μ ≠ 37
μ = 37 ; σ = 7 ; sample size, x = 51 ; sample size, n = 1
Decision region :
If P value < α ;
Reject H0
Using the Z test statistic :
Zstatistic = (x - μ) ÷ (σ / √n)
Zstatistic = (51 - 37) ÷ (7 / 1)
Zstatistic = 14 ÷ 7
Zstatistic = 2
Obtaining p value from Zstatistic using the p value calculator ;
Zscore = 2 ; 2-tailed test, significance level = 0.05
P value = 0.0455
Zcritical at α = 0.05 for a 2 - tailed test = 1.96
0.0455 < 0.05
There is significant evidence that treatment will create effect on the subject. Hence We reject H0