Answer:
a) 0.0016
b) 0.0224
Step-by-step explanation:
If every question has 5 possible answers, the probability of getting the correct answer by guessing would be 0.20. The probability of getting an incorrect answer would be 0.80.
a)Find the probability she lucks out and answers all four questions correctly.
To do this, Allison would have to guess right the first, second, third AND fourth answers. Therefore, we have to multiply the probabilities:
0.20 x 0.20 x 0.20 x 0.20 = 0.0016
The probability that she answers all 4 questions correctly is 0.0016.
b) Find the probability that she passes the quiz.
To pass the quiz, she has to have three OR 4 correct answers:
- The probability that she has 3 correct answers is: 0.20 x 0.20 x 0.20 x 0.80 (since she has to have 1 correct answer and 1 incorrect one) = .0064.
- We already calculated the probability that she guesses 4 answers correctly: 0.0016.
Now, we have to sum up these two scenarios:
0.0064 + 0.016 = 0.0224.
Thus, the probability that she passes the quiz is 0.0224
Answer:
22
Step-by-step explanation:
Pretend the 10 values in the first sentence are a,b,c,d,e,f,g,h,i,j
Pretend the addition 5 values is k,l,m,n,o
So the mean of all the 15 data is (a+b+c+d+e+f+g+h+i+j+k+l+m+n+o)/15=20
So the sum of all 15 data is a+b+c+d+e+f+g+h+i+j+k+l+m+n+o=300 since 15(20)=300
Now let's look at the first 10: We have their mean so we can write:
(a+b+c+d+e+f+g+h+i+j)/10=19
so a+b+c+d+e+f+g+h+i+j=190 since 10(19)=190
So that means using our first sum equation and our equation sum equation we have
190+k+l+m+n+o=300
k+l+m+n+o=300-190
k+l+m+n+o= 110
So the average of those 5 numbers mentioned in your problem is 110/5=22
Answer:
x = 387
Step-by-step explanation:
The wind acts in the opposite direction to the plane when the time is longer.
The wind acts in the same direction as the plane when the time is shorter.
Equation
d = r*t
Givens
- d = 1720
- x = plane's speed
- y = wind speed
- t1 = 5 hours
- t2 = 4 hours.
Substitution
- d = (x + y) * t
- 1720 = (x + y) * 4
- 1720 = (x - y) * 5
Since the two distances are the same, you can equate the right hand sides.
- (x + y) * 4 = (x - y)*5 Remove the brackets.
- 4x + 4y = 5x - 5y Add 5y to both sides
- 4x + 4y + 5y = 5x - 5y + 5y Combine all the terms.
- 4x + 9y = 5x Subtract 4x from both sides
- 9y + 4x - 4x = 5x - 4x Combine
- 9y = x
Now use one of the given equations with the distance
- 1720 = (x + y)*4 Substitute 9y for x
- 1720 = (9y + y) * 4 Combine
- 1720 = 10y * 4 Multiply the right
- 1720 = 40y Divide by 40
- 1720/40 = 40y/40 Do the division
- 43 = y y = wind speek
- 9y = x x = 9*y
- 9*43 = x
- x = 387 miles per hour.
Answer: 0,-3
Step-by-step explanation: hope this helps!!
Answer:
530.66
Step-by-step explanation:
to find the area you need to do pi times the radius square and to find the radius squared you just times it by its self so 13 times 13 which is 169 and pi is 3.14
so now you just do 3.14x169=530.66
