You have unlimited supply of 1¢, 5¢, 10¢, 25¢ and 50¢ (penny, nickel, dime, quarter, half-dollar respectively) coins. What is the fewest number of coins required to have an exact change for all possible items that cost from one cent up to and including one dollar in one-cent increments?

Riddle Answer# Math Riddles

## Ten Years Older

There are two brothers whose combined age is eleven years. One is ten years older than the other. What are their ages?

They are 10.5 and 0.5 years old.

A common wrong answer is 10 and 1. This is wrong because the difference in age would be 9, not 10.

## Mr Tan’s Birthday

Ben and Mark are students of Mr Tan. Mr Tan’s date of birth is on N/M/1970 and both of them know that Mr Tan’s birthday is one of these 10 dates:

4/3/1970 5/3/1970 8/3/1970 4/6/1970 7/6/1970 1/9/1970 5/9/1970 1/12/1970 2/12/1970 8/12/1970

Mr Tan tells Ben the value of M and tells Mark the value of N. Then Mr Tan asks them: “Do you know when my birthday is?”

Ben says: “I don’t know, but I can be sure that Mark doesn’t know either.”

Mark says: “Initially I don’t know, but now I do.”

Ben says: “Oh, then now I know it too.”

Based on this dialogue and the dates given, can you figure out which is the correct date of Mr Tan’s birthday?

Riddle Answer## Sabrina and Samantha

Sabrina gave Samantha as many dollars as Samantha started out with. Samantha then gave Sabrina back as much as Sabrina had left.

Sabrina then gave Samantha back as many dollars as Samantha had left, which left Sabrina broke and gave Samantha a total of $80.00. How much did Sabrina and Samantha have at the beginning of their exchange?

Riddle Answer