Answer:
Therefore, the probability that at least half of them need to wait more than 10 minutes is <em>0.0031</em>.
Step-by-step explanation:
The formula for the probability of an exponential distribution is:
P(x < b) = 1 - e^(b/3)
Using the complement rule, we can determine the probability of a customer having to wait more than 10 minutes, by:
p = P(x > 10)
= 1 - P(x < 10)
= 1 - (1 - e^(-10/10) )
= e⁻¹
= 0.3679
The z-score is the difference in sample size and the population mean, divided by the standard deviation:
z = (p' - p) / √[p(1 - p) / n]
= (0.5 - 0.3679) / √[0.3679(1 - 0.3679) / 100)]
= 2.7393
Therefore, using the probability table, you find that the corresponding probability is:
P(p' ≥ 0.5) = P(z > 2.7393)
<em>P(p' ≥ 0.5) = 0.0031</em>
<em></em>
Therefore, the probability that at least half of them need to wait more than 10 minutes is <em>0.0031</em>.
Answer:
Step-by-step explanation:
In No.1
First you find the total number of girls which is 56-20 =36 girls in total
So to get number of boys who watched tennis 20-13=7 boys watched tennis
To get number of girls who didnt watch you do 36-17=19 girls who watched
Then add o get the totals
No.2
First you get the total number of male 80-47=33 males
Next you find the number of females doing phyisics 33-19=14 females
Next you find the number of females doing chemistry by 47-(18 + 14)=15 females
To get the number of males diong chemistry 21-15=6 males
Number of males doing biology 33-(19+6)=8
Then find the remaining totals
2
No. 2 (b)
Because there is a high number of students doing physics and most of them are female
Answer: $400
Step-by-step explanation:
So first you set it up in a equation. You put the amount she put in the bank over x (the x represents her full salary) which equals the percent she already spent over her full salary. That would be 120/x=30/100 you would then cross-multiply to get 12,000 = 30x. you then divide 30 from both sides to get x =400.
Answer:
Company B pays more!
Step-by-step explanation:
All you have to do is...
25,000x10=250,000
+
1,600x10=16,000
= 266,000(company a)
28,500x10=285,000
+
700x10=7,000
= 292,000(company b)
Answer:
y=−2x+4
Step-by-step:
2y+4x=8
Step 1: Add -4x to both sides.
4x+2y+−4x=8+−4x
2y=−4x+8
Step 2: Divide both sides by 2.
2y
/2
=
−4x+8
/2
y=−2x+4