Question

Question 2
Tom invites Maggie for a party. Maggie knows that on her way to Tom's house, she will come across 4 lanes. There
are five houses at the end of each lane. One of the five houses is Tom's. What is the probability that the first house
that Maggie checks is not Tom's?

Answer 1

Given: Tom invites Maggie for a party. Maggie knows that on her way to Tom's house, she will come across 4 lanes. There are five houses at the end of each lane. One of the five houses is Tom's.

To find: The probability that the first house that Maggie checks is not Tom's.

Solution:

According to the question, there are five lanes and at the end of each lane, there are five houses. Since Maggie has to cross four lanes before she reaches Tom's house, it is evident that Tom's house is in the 5th lane.

Now the first lane has 5 houses and one of them is Tom's. Thus, the number of favourable outcomes is 1 and the number of total possible outcomes is 5. So, the probability is given as follows.

$P(E) = \frac{1}{5}$

Therefore, the probability that the first house that Maggie checks is not Tom's is 1/5.