Answer:
Step-by-step explanation:
The formula for determining confidence interval is expressed as
Confidence interval
= mean ± z × s/ √n
Where
z is the value of the z score
s = standard deviation
n = sample size
a) The 95% confidence level has a z value of 1.96
The 99% confidence level has a z value of 2.58
Since 99% confidence level z value is greater than 95% confidence level z value, if we input it into the formula, it will result to a higher confidence interval. So changing from a 95% confidence level to a 99% confidence level would make a confidence interval wider.
b) The √15 is smaller than the √350. This means that if we make use of the formula, √350 will give a lower confidence interval than that of √15. Therefore, the confidence interval would be narrower changing from a sample size of 15 to a sample size of 350.
c) Applying the formula, a standard deviation of 15 pounds would result to a lower confidence interval than a standard deviation of 20 pounds. Therefore, the confidence interval would be wider changing from a standard deviation of 15 pounds to a standard deviation of 20 pounds.
Answer:
see explanation
Step-by-step explanation:
The hypotenuse is the longest side thus is (4x + 1)
The legs are 2x and (4x - 1)
Using Pythagoras' theorem, then
(4x + 1)² = (2x)² + (4x - 1)² ← expanding factors
16x² + 8x + 1 = 4x² + 16x² - 8x + 1 , that is
16x² + 8x + 1 = 20x² - 8x + 1 ( subtract 20x² - 8x + 1 from both sides )
- 4x² + 16x = 0 ( multiply through by - 1 )
4x² - 16x = 0 ← factor out 4x from each term
4x(x - 4) = 0
Equate each factor to zero and solve for x
4x = 0 ⇒ x = 0
x - 4 = 0 ⇒ x = 4
Now x > 0, thus x = 4
2x = 2(4) = 8
4x - 1 = 4(4) - 1 = 16 - 1 = 15
4x + 1 = 4(4) + 1 = 16 + 1 = 17
Thus
perimeter = 8 + 15 + 17 = 40 cm
Answer:
measure it bro lol
Step-by-step explanation:
Answer:
a = -3.5
Explanation:
2 - 4a = 16
-4a = 14
a = -3.5
