Answer:
The answer is below
Step-by-step explanation:
1)
mean (μ) = 12, SD(σ) = 2.3, sample size (n) = 65
Given that the confidence level (c) = 90% = 0.9
α = 1 - c = 0.1
α/2 = 0.05
The z score of α/2 is the same as the z score of 0.45 (0.5 - 0.05) which is equal to 1.65
The margin of error (E) is given as:

The confidence interval = μ ± E = 12 ± 0.47 = (11.53, 12.47)
2)
mean (μ) = 23, SD(σ) = 12, sample size (n) = 45
Given that the confidence level (c) = 88% = 0.88
α = 1 - c = 0.12
α/2 = 0.06
The z score of α/2 is the same as the z score of 0.44 (0.5 - 0.06) which is equal to 1.56
The margin of error (E) is given as:

The confidence interval = μ ± E = 23 ± 2.8 = (22.2, 25.8)
9. she spends 1 hour total and 1/2 hour on spanish. So she has another 1/2 on another subject ( as she spends equal time on each subject)
So number of subjects = 1 / 1/2 = 1 * 2 = 2
Answer:
ok
Step-by-step explanation:
Answer: Simple and best practice solution for 4y^2+8y+1=0 equation. ... Begin completing the square. ... Square it (1) and add it to both sides.
Step-by-step explanation: Complete the square for x2+2x x 2 + 2 x.