This is not my answer I found it from another brainly
From the beginning we know we are dealing with two different rates. Distance is equal to (Speed X Time). We have two different speeds though. We will call the min speed = x and the max speed = y. With those two ideas in place we can make two equations for both Tony and Rae.
Tony:
2x+3.5y=355
Rae:
2x+3y=320
Now you can solve the equations by subtracting Rae's equation from Tony's
.5y=35 solve for y and you get 70
Now plug that y value back into either equation and you can solve for x. I'll use Rae's distance:
2x+3(70)=320
x=55
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.
Answer:

Step-by-step explanation:

Make sure they have a common denominator. To do so, you must find a number the both have in come. Here, the number they have in common is 20.
What times 4 equals 20? 5. Whatever you do to the denominator you must do to the numerator.
×
= 
Now you have
= 
Then you can simplify
to
by dividing it by 
Included a pic of the solution and work.
Answer:
64,120,136
I think
Step-by-step explanation: