Let the speed of the boat be x
so going against the current the speed is x-7
going with the current the speed is x+7
let the distance be d
time = distance / speed
time to go against the current = d/(x-7)
time to go with the current = d/(x+7)
time going against the current is 3 times going <span>with the current
</span>
d/(x-7) = 3d/(x+7)
⇒⇒⇒ divide by d
1/(x-7)
= 3/(x+7)
x+7
= 3(x-7)
x+7 = 3x - 21
2x = 28
x = 14
So, the speed of the boat in still water is = 14 mph
Answer:
Step-by-step explanation:
Meeting ID: 621 872 6773
Passcode: UL4qmA
Y=-11. 2×-4 is -8, and -8-3 is -11.
Answer:
0.0498 = 4.98%
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given time interval.
Inquiries arrive at a record message device according to a Poisson process of rate 15 inquiries per minute.
Each minute has 60 seconds.
So a rate of 1 inquire each 4 seconds.
The probability that it takes more than 12 seconds for the first inquiry to arrive is approximately
Mean of 1 inquire each 4 seconds, so for 12 seconds 
This probability is P(X = 0).


The answer is 20.1.
<em>**Please mark this answer as Brainliest and leave a Thanks if I helped :)</em>