Answer: The answer is -19.
Step-by-step explanation: We are given to write the numerical coefficient of -9x.
The given expression is a monomial with unknown variable 'x'.
We know that a numerical coefficient of a monomial is a constant multiplied to the variable(s). For example, in the term -5xy, the unknown variables are 'x' and 'y' and the numerical coefficient is -5.
Therefore, in -9x, the unknown variable is 'x' and the numerical coefficient is -9.
Thus, the answer is -9.
Answer:
The percent of the parts are expected to fail before the 2100 hours is 0.15.
Step-by-step explanation:
Given :Life tests on a helicopter rotor bearing give a population mean value of 2500 hours and a population standard deviation of 135 hours.
To Find : If the specification requires that the bearing lasts at least 2100 hours, what percent of the parts are expected to fail before the 2100 hours?.
Solution:
We will use z score formula

Mean value = 
Standard deviation = 
We are supposed to find If the specification requires that the bearing lasts at least 2100 hours, what percent of the parts are expected to fail before the 2100 hours?
So we are supposed to find P(z<2100)
so, x = 2100
Substitute the values in the formula


Now to find P(z<2100) we will use z table
At z = −2.96 the value is 0.0015
So, In percent = 
Hence The percent of the parts are expected to fail before the 2100 hours is 0.15.
P(8 or 12) = 1/6
P(not 8 or 12 = 5/6
Let the expected points fro one roll be X.

The answer is -(1/6) points.
Answer:
174 rpm
Step-by-step explanation:
The question says that the speed is inversely proportional to the length. Thus, Inverse means, as the diameter increases, the speed reduces, or as the diameter reduces, the speed increases.
Thus, from the question, if diameter A is 20, and B is 10, then definitely, the speed will increase from 348 to a higher rate. Mathematically, we have
20 / 10 = 348 / x, where x is the missing speed.
2 = 348 / x
x = 348 / 2
x = 174 rpm
Therefore, the pulley A must have been running at a speed of 174 rpm