Answer:
Step-by-step explanation:
Let 'x' be the original price.
x + 39% of x = 197.38
x + 0.39 x = 197.38
1.39x = 197.38
x = 197.38/ 1.39
x = 142
Answer:
-9x^9y^5
Step-by-step explanation:
Do the multiply first:
-16x^9y^5+7x^9y^5
=x^9y^5(-16+7)
=-9x^9y^5
Answer: volume of pyramid is
100 ft.3
Step-by-step explanation:
The formula for determining the volume of triangular Pyramid is expressed as
Volume = 1/3AH
Where
A represents the area of the triangular base of the pyramid
H represents the height of the pyramid.
The triangular Pyramid has a base of 10 square feet and a height of 30 feet. Therefore,
Volume = 1/3 × 10 × 30 = 100 cubic feet
Answer:
Step-by-step explanation:
We want to determine a 95% confidence interval for the mean salary of all graduates from the English department.
Number of sample, n = 400
Mean, u = $25,000
Standard deviation, s = $2,500
For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean ± z × standard deviation/√n
It becomes
25000 ± 1.96 × 2500/√400
= 25000 ± 1.96 × 125
= 25000 ± 245
The lower end of the confidence interval is 25000 - 245 =24755
The upper end of the confidence interval is 25000 + 245 = 25245
Therefore, with 95% confidence interval, the mean salary of all graduates from the English department is between $24755 and $25245
