<u>Answer:</u>
Distance = 3r
<u>Step-by-step explanation:</u>
We are to write an algebraic expression and then simplify it for the given situation:
<em>The distance traveled by a train in three hours with a constant speed of r miles per hour.</em>
We know the formula of distance linking the speed and the time.
Distance = speed × time
Substituting the given values to get:
Distance = r × 3
Distance = 3r
Answer:
Option d) 840
Step-by-step explanation:
Given that a test to measure psychotic tendencies was given to a group of 1,000 air force cadets who wished to work in nuclear silos.
If Score ≥64 would be eliminated.
X is N(52, 12)
Probability for any random person to get eliminated
=
Now coming to sample size of 1000 people, we find each person is independent of the other and there are two outcomes either >64 or < 64
So Y no of persons who get more than 64 is binomial with n =1000 and p = 0.1587
Mean of Y = E(Y)
= no of people who were not accepted 
No of people accepted 
Approximately we get 840 so option d
Answer:
The probability of drawing a red marble = 2/5. The probability of drawing a blue marble is now = 1/4.
Step-by-step explanation:
There are 2 ways to do this....
(1) 20(1.15) = 23
(2) 20 + 0.15(20) = 20 + 3 = 23