Answer:
d. 20
Step-by-step explanation:
Standard deviation is 4.5
Margin error for the problem is 2 hours
Probability 95%, that means that the siginficance level α is 1 – p
α = 1 – 0.95 = 0.05
margin of error (ME) can be defined as follows
ME = Z(α/2) * standard deviation/ √n
Where n is the sample size
Z(0.05/2) = Z(0.025)
Using a z table Z = 1.96
Now, replacing in the equation and find n
2 = 1.96 * 4.5/ √n
2 = 8.82/√n
√n = 8.82/2
√n = 4.41
n = 4.41^2
n = 19.44 ≈ 20
0.20/0.70 = 0.2857
28.6% chance
round the answer as needed.
Answer:
2 is the answer
Step-by-step explanation:
its like
(square root 2)^2
{square root and whole square is cancelled and 2 is the answer}
<span>p = 39/52 = 3/4 = 0.75
</span>
13 cards each of 4 different suits
if you draw a card, there are 39 cards that
are not hearts out of 52 all together.
You flip the second fraction and you multiply. 1 and 2/5 or 1.4