Answer:
12
Step-by-step explanation:
The first cave has 7 times more bats than the last cave. So if the 45th cave has b bats, then the first cave has 7b bats.
There are 77 bats in every row of 7 caves. So if there are 7b bats in the first cave, then there are 77−7b bats in caves 2 through 7.
Since there are also 77 bats in caves 2 through 8, that means cave #8 must have 7b bats. Repeating this logic:
#1 = 7b
#2-#7 = 77−7b
#8 = 7b
#9-#14 = 77−7b
#15 = 7b
#16-21 = 77−7b
#22 = 7b
#23-28 = 77−7b
#29 = 7b
So the first 29 caves have 5(7b) + 4(77−7b) = 308 + 7b bats.
Now we do the same thing from the other end. If cave #45 has b bats, then caves #39-#44 have 77−b bats. And since caves #38-44 have 77 bats, then cave #38 has b bats. Therefore:
#45 = b
#39-44 = 77−b
#38 = b
#32-37 = 77−b
#31 = b
So caves 31 through 45 have 3b + 2(77−b) = 154 + b bats.
Adding that to the first 29 caves, plus x number of bats in cave #30:
308 + 7b + x + 154 + b = 462 + 8b + x
We know this equals 490.
490 = 462 + 8b + x
28 = 8b + x
x is a maximum when b is a minimum, which is b = 2.
28 = 8(2) + x
x = 12
There are at most 12 bats in the 30th cave.
Parallel lines have equal slopes.
-x + y = 5
y = x + 5
Slope = 1
y + 5 = 1(x - 2)
y + 5 = x - 2
y = x - 2 - 5
y = x - 7
Answer: Choice A
Answer:
Hence the person stop at floor by at least one person will be
E(X)=(summation from K=1 to k)[1-{(k-1)/k}^n]
Step-by-step explanation:
Given:
There are n peoples and k floors in a building.
Selects floor with 1/k probability .
To find :
Elevator stop at each floor by at least one person.
Solution:
Now
let K= number of floor at which at least one person will be stopping.
For getting E(X)
consider a variable Ak =1 if a least one person get of the elevator
and values for k=1,2,3.....k
K=(summation From k=1 to k)Ak
E(K)=((summation From k=1 to k) E[Ak]
=(summation From k=1 to k)[
Hence the person stop at floor by at least one person will be
E(K)=(summation from K=1 to k)[1-{(k-1)/k}^n]
Answer: The numbers are -3 and 2
Step-by-step explanation: Let x be the first number and y be the second number
then according to given statements the linear equations will be:
"Four times a number minus twice another number is -16"
"The sum of the two numbers is -1"
From equation 2:
Putting y = -x-1 in equation 1
Subtracting 2 from both sides
Dividing both sides by 6
Putting x = -3 in equation 2:
Hence,
The numbers are -3 and 2
The answer is C because multiplication comes first
