Homework on Probability Question

Question

There is a 85% chance that Josh goes to the mall on Saturday. Otherwise he will go to the movies. Either way, there is a 25% chance that he brings a date.

 

a.) What is the probability that he goes to the mall with no date?

 

 

c.) What is the probability that he goes anywhere with a date?

Answer 1

The best approach to a problem that is complex or contains multiple probabilities is to see how they intersect or are dependent upon each other.  Read the question once through before answering.  Josh has an 85% chance that he will go to the mall on Saturday and a 25% chance that he will bring a date.  So...25% of whatever he is doing he will have a date and 75% chance he will have no date.  Since there is an 85% chance he will go to the mall and with no date then take 75% of 85%...which in math "of" usually means times or the product of...now here is the math...for a)

 

a) 75% x 85% = 63.75%  

 

For c) What is the probability that he goes anywhere with a date?   This is more of a word problem since the original information reads "Either way, there is a 25% chance that he brings a date."  Therefore, Josh always has a 25% chance that he brings a date with him.  The answer is 25%.