Answer:
we will fail to reject the null hypothesis and conclude that the mean pressure is not different from 4.7 psi
Step-by-step explanation:
Let's first define the hypothesis;
Null hypothesis: H0: μ = 4.7
Alternative hypothesis: Ha: μ ≠ 4.7
We have;
Sample size; n = 110
Sample mean; x¯ = 4.6
Variance: σ² = 0.64
Standard deviation; σ = √0.64 = 0.8
Formula for test statistic is;
z = (x¯ - μ)/(σ/√n)
z = (4.6 - 4.7)/(0.8/√110)
z = -0.1/0.0763
z = -1.31
From online p-value from z-score calculator attached, using; z = -1.31, two tailed hypothesis, significance value of 0.1, we have;
P-value = 0.190196
The p-value is greater than the significance value and thus we will fail to reject the null hypothesis and conclude that the mean pressure is not different from 4.7
σ μ
Answer: he invested $46062.5 at 6% and $23031.25 at 10%
Step-by-step explanation:
Let x represent the amount which he invested in the account paying 6% interest.
Let y represent the amount which he invested in the account paying 10% interest.
He puts twice as much in the lower-yielding account because it is less risky.. This means that
x = 2y
The formula for determining simple interest is expressed as
I = PRT/100
Considering the account paying 6% interest,
P = $x
T = 1 year
R = 6℅
I = (x × 6 × 1)/100 = 0.06x
Considering the account paying 10% interest,
P = $y
T = 1 year
R = 10℅
I = (y × 10 × 1)/100 = 0.1y
His annual interest is $7370dollars. it means that
0.06x + 0.2y = 7370 - - - - - - - - - -1
Substituting x = 2y into equation 1, it becomes
0.06 × 2y + 0.2y = 7370
0.12y + 0.2y = 7370
0.32y = 7370
y = 7370/0.32
y = $23031.25
x = 2 × 23031.25
x = 46062.5
Answer:


Step-by-step explanation:
We are given


Calculation of P+Q:

now, we can combine like terms



Calculation of Q-P:

Firstly, we will distribute negative sign

now, we can combine like terms


Answer:
-4
Step-by-step explanation:
-10 - (-6)
Remove the brackets:
-10 - - 6
Remember that all negative and negative values are always positive because they are the same; if they are different, for instance, a positive value and a negative value, then that value will be a negative value.
Continue solving:
-10 - - 6
- and - are positive values
- 10 + 6
= - 4
Therefore the answer is 4