Answer: They cost the same amount.
Step-by-step explanation:
35(0.20)=7
35-7=28
40(0.30)=12
40-12=28
28=28
Answer:
Step-by-step explanation:
Assuming a normal distribution we find the standardized z scores for a:-
z1 = (80 - 180) / 25 = = -100/25 = -4
z2 = (280-180) / 25 = 4
Required P( -4 < z < 4) from the tables is >99.9%
b
z1 = 130-180 / 25 = -2
z2 = 230-180 / 25 = 2
from tables probability is 2* 0.4773 = 95.46 %
Answer:
Number of students in district = 3,055 students
Step-by-step explanation:
Given:
Ratio [Teachers to students] = 2 : 47
Total number of teachers in district = 130
Find:
Number of students in district
Computation:
Number of students in district = Total number of teachers in district[47/2]
Number of students in district = 130[47/2]
Number of students in district = 65[47]
Number of students in district = 3,055 students
Answer:
a) P value = 0.0013
b) No, it is not plausible that the silicon content of the water is no greater than it was 10 years ago
Step-by-step explanation:
The null hypothesis here is “Mean is equal to 5” while alternate hypothesis is that “Mean is greater than 5”
Given
Mean = 5, x’ = 5.4 and sigma = 1.2 and n = 85
Z = x-u’/sigma/sqrt n
Substituting the given values, we get –
Z = 3.02
A) P value = 0.0013 which is less than 0.05 and thus we will reject the null hypothesis
B) There is enough evidence to reject the null hypothesis
