Step-by-step explanation:
We want to compare the means, so find the difference and the corresponding standard deviation:
μ = μ₁ − μ₂
μ = 25 − 23
μ = 2
σ = √(σ₁²/n₁ + σ₂²/n)
σ = √(3.1²/50 + 3.2²/50)
σ = 0.63
Using a 95% confidence level, z = 1.96. So the interval is:
CI = 2 ± 1.96 × 0.63
CI = 2 ± 1.2
There is a 95% probability that the true difference in means is between 0.8 and 3.2. Since 0 is not in this interval, we can conclude that there is a significant difference between the commute times for the two populations.
Answer:
Step-by-step explanation:
y = 3x + 0
y = 1/2x + 0
y = 3x + 0
-3x -3x
y - 3x = 0
y = 1/2x + 0
2(y = 1/2x + 0)
2y = x + 0
-x -x
2y - x = 0
y - 3x = 0
2y - x = 0
1(y - 3x = 0) = y = - 3x = 0
-3(2y - x = 0) = -6y + 3x = 0
y = - 3x = 0
-6y + 3x = 0
-5y = 0
/-5 /-5
y = 0
y = 3x + 0
0 = 3x + 0
-3x -3x
-3x + 0 = 0
- 0 -0
-3x = 0
/-3 /-3
x = 0
(x,y) -> (0, 0)
Hope this helps!
Answer: f(x) = -13
Step-by-step explanation:
Answer:
= - 1.5n - 6
Step-by-step explanation:
Given that the sequence is arithmetic with n th term ( explicit formula
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = - 7.5 and d = - 9 - (- 7.5) = - 9 + 7.5 = - 1.5
= - 7.5 - 1.5(n - 1) = - 7.5 - 1.5n + 1.5 = - 1.5n - 6
Step-by-step explanation: