Answer:
For equation 21-b=11 given in the statement
the answer is b=10
Step-by-step explanation:
This is the equation: 21-b=11
If we sum '-21' to both sides of equation, we have
21-b-21=11-21, which leaves us to: -b=-10
Now lets multiply the equation from above by '-1', we obtain that b=10
Answer:
The t value for 99% CI for 21 df is 2.831.
The critical value that should be used in constructing the confidence interval is (64.593, 86.407).
Step-by-step explanation:
Now the sample size is less than 30 and also population standard deviation is not known.
Then we will use t distribution to find CI
t value for 99% CI for 21 df is TINV(0.01,21)=2.831
The margin of error is 
Hence CI is
The length of the rectangle is 10 cm and perimeter of the rectangle is 32 cm.
Step-by-step explanation:
Given,
The area of rectangle = 60 sq cm
Width (b) of the rectangle = 6 cm
To find the length and perimeter of the rectangle.
Formula
The area of the rectangle = l×b
The perimeter of the rectangle = 2(l+b)
According to the problem,
l×b = 60
or, l×6 = 60
or, l = 60÷6 = 10
Length (l) = 10 cm
Perimeter = 2×(10+6) cm = 32 cm
The probability of 3 failures or less is about 0.83886, so that is the probability the machine will be working.
Answer: 38 cm
Step-by-step explanation:
