Answer:
a) Mean = 382.3 psi
Standard deviation = 20.8 psi
b) 392.7 psi
c) P(X<400)=0.8026
Step-by-step explanation:
a) The population mean can be estimated as equal to the mean of the sample, and the population standard deviation can be estimated from the sample standard deviation:
b) We start by searching for the z-value for the 95th percentile. This value is
z=1.645:
Then, the strength value below which 95% of all welds will have their strengths is:
c) We calculate the probability of X being equal or less than 400 as:
To find this answer you would use the formula for finding the volume of a cylinder. Because both of these cylinders are congruent, the area of the base for cylinder A I would also be the same area for cylinder B. V=pi x r^2 x h. When we substitute in what we know this is the new equation: 27 x pi = pi x r^2 x 3. Divide both sides by three and pi. This gives us 9 = r^2. Take the square roots of both sides to find the radius. The answer would be 3. Now use the formula for area of a circle to find the area of the base of cylinder B. A= pi x r^2. So the area would be 9 x pi.
Answer:
A rectangular prism has eight vertices and a rectangular pyramid has five.Step-by-step explanation:
Answer:
Nearest ten-350
Nearest hundred-300
Step-by-step explanation:
#When rounding to the nearest ten, we look at the ones digits in a number:
- If the ones digit is 0, 1, 2, 3, or 4, you will round down to the previous ten
- If the ones digit is 5, 6, 7, 8, or 9, you will round up to the next ten
Given the number 348, 8 in the ones digit greater than 4 so we round to the next ten:
348 ≈350
#When rounding to the nearest hundred, we look at the tens digits in a number:
- If the ones digit is less than 5 you will round down to the previous hundred
- If the ones digit is greater than 4, you will round up to the next hundred
Given the number 348, 4 in the tens digit less than 5 so we round down to the previous hundred:
348 ≈300
