Answer:
Step-by-step explanation:
Hello!
X₁: speed of a motorcycle at a certain intersection.
n₁= 135
X[bar]₁= 33.99 km/h
S₁= 4.02 km/h
X₂: speed of a car at a certain intersection.
n₂= 42 cars
X[bar]₂= 26.56 km/h
S₂= 2.45 km/h
Assuming
X₁~N(μ₁; σ₁²)
X₂~N(μ₂; σ₂²)
and σ₁² = σ₂²
<em>A 90% confidence interval for the difference between the mean speeds, in kilometers per hour, of motorcycles and cars at this intersection is ________.</em>
The parameter of interest is μ₁-μ₂
(X[bar]₁-X[bar]₂)±
* 
[(33.99-26.56) ± 1.654 *(
)]
[6.345; 8.514]= [6.35; 8.51]km/h
<em>Construct the 98% confidence interval for the difference μ₁-μ₂ when X[bar]₁= 475.12, S₁= 43.48, X[bar]₂= 321.34, S₂= 21.60, n₁= 12, n₂= 15</em>
[(475.12-321.34) ± 2.485 *(
)]
[121.96; 185.60]
I hope this helps!
Answer:
Answer:
Option B is correct.
Miguel should study for the Science quiz as he will do worse in that quiz by guessing.
Step-by-step explanation:
Miguel has to take two quizzes
1) 4 true or false questions on History with a 0.5 chance of acing the quiz
Expected number of correct questions = np
n = number of questions
p = probability of acing the test
Expected number of correct questions = 4 × 0.5 = 2
2) 3 multiple choice questions on Science with a 0.2 chance of acing the quiz.
Expected number of correct questions = 0.2 × 3 = 0.6
It is evident that guessing would yield a worse result in the Science quiz with less than 1 question expected to be correct than history, where he is still expected to get 2 questions correctly by guessing.
Answer:
Step-by-step explanation:
Starting from the top, the ant can only take four different directions, all of them going down, every direction has a probability of 1/4. For the second step, regardless of what direction the ant walked, it has 4 directions: going back (or up), to the sides (left or right) and down. If the probability of the first step is 1/4 for each direction and once the ant has moved one step, there are 4 directions with the same probability (1/4 again), the probability of taking a specific path is the multiplication of the probability of these two steps:
There are only 4 roads that can take the ant to the bottom in 2 steps, each road with a probability of 1/16, adding the probability of these 4 roads:
The probability of the ant ending up at the bottom is 
or 0.25.
Answer:
12a^9b^7
Step-by-step explanation:
Multiplying variables of the same base, will require you to add the exponents.
4a^3b^2 * 3a^6b^5
4*3 = 12
a^3 * a^6 = a^9
b^2 * b^5 = b^7
12a^9b^7
