Question??
Dr. Sox drives through two stoplights on her way to work. The first light is green for 20 seconds out of each minute. The second light is green for 35 seconds out of each minute. What is the probability that Dr. Sox will hit two green lights?
Explanation;
Since this is an AND situation, we MULTIPLY the probabilities.
Answer/Explanation:
First light green:
P
1
=
20
60
=
1
3
Second light green:
P
2
=
35
60
=
7
12
Both lights green:
P
=
P
1
×
P
2
=
1
3
×
7
12
=
7
36
Of course, this is assuming that there is no "green wave" policy, or the two probabilities would not be independent
Answer: 8
Step-by-step explanation: the given expression is 2n-3
so when n=1, we will get, 2(1)-3=2-3=-1
when n=2, we will get, 2(2)-3= 4-3=-1
when n=3, we will get 2(3)-3= 6-3=3
when n=4, we will get 2(4)-3 = 8-3=5
so the required result of expansion is -1+1+3+5=8
answer is 8.
hope that helped!
Answer:
-2
Step-by-step explanation:
Let x be the unknown value
Log₆ ( 1/36) = x
( 1/36) = 36⁻¹ = (6²)⁻¹ = 6⁻²
Log₆ ( 1/36) = Log₆
6⁻² = -2 Log₆
6
Log₆
6 = 1
-2 Log₆
6 = -2(1) = -2
There are 6! possible permutations of the blue books, 2 possible permutations of the red books, 4! possible permutations of the green books and 3! possible permutations of the three color groups. therefore the total number of ways of arranging the books is given by:
We're going to be using combination since this question is asking how many different combinations of 10 people can be selected from a set of 23.
We would only use permutation if the order of the people in the committee mattered, which it seems it doesn't.
Formula for combination:

Where
represents the number of objects/people in the set and
represents the number of objects/people being chosen from the set
There are 23 people in the set and 10 people being chosen from the set


Usually I would prefer solving such fractions by hand instead of a calculator, but factorials can result in large numbers and there is too much multiplication. Using a calculator, we get

Thus, there are 1,144,066 different 10 person committees that can be selected from a pool of 23 people. Let me know if you need any clarifications, thanks!
~ Padoru