Question

An apartment building has the following distribution of apartments:

1 bedroom 2 bedroom 3 bedroom
1st floor 3 1 1
2nd floor 2 2 2
3rd floor 1 4 1
If an apartment is selected at random, what is the probability that it is on the 2nd floor or has 2 bedrooms?
A) 7/11
B) 6/11
C) 13/17
D) 11/17

Answer 1

To calculate the probability of selecting the probability of any apartment is 1/3. But we won't take it into account.

Also, to be on the second floor the probability comes out to be 6/17

Furthermore, selecting a 2 bedroom apartments probability comes out to be 7 /17.

So finally you can add all of them as they are independent events. 6/17 + 7/17/ = 13/17.

Hence the answer is C. 13/17

Answer 2

The correct answer is C) 13/17.

Step-by-step explanation:
From the two-way table, we find the total number of 2nd floor apartments is 2+2+2=6.
The total number of 2-bedroom apartments is 1+2+4=7.
The total number of apartments altogether is 3+1+1+2+2+2+1+4+1=17.

There are 13 apartments that are either on the 2nd floor or 2-bedroom out of 17 total, so the probability is 13/17.