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)
The Pyth. Thm. applies here:
(√x + 1)^2 + (2√x)^2 = (2√x + 1 )^2
Expanding the squares:
x + 2sqrt(x) + 1 + 4x = 4x + 4sqrt(x) + 1
Let's subtract x + 2sqrt(x) + 1 + 4x from both sides:
4x + 4sqrt(x) + 1
-(x + 2sqrt(x) + 1 + 4x)
-------------------------------
3x + 2sqrt(x) - 4x = 0
Then 2sqrt(x) = x
Squaring both sides, 4x = x^2, or x^2 - 4x = 0. Then (x-4)x = 0, and the two possible solutions are 0 and 4.
Check these results by substitution. Does the Pyth. Thm. hold true for x=4?
12 + 5 = P + 360° - (90° x 2)
17 = 360°P - 180°
17 = 180° => P = 180° - 90° = 90° => P - 5 = P + (5 + 12) => P = 14 in <90 5 CM Angle, P = 14 - 1 = 13 without offset
13
The width is 4. 6lx5hx4w=120 volume
Answer:
75%
Step-by-step explanation:
$39= x-(0.25x)= 0.75x
A 25% discount takes off 0.25 of the price.
x= original price
To find the original we use something like the above equation