perplexus.info :: Just Math : The Change Machine

The Change Machine (Posted on 2025-05-01)

While on vacation, Jenny encountered a strange change machine. Given a nickel, the machine outputs five pennies; given a dime, the machine outputs two nickels; given a quarter, the machine outputs two dimes and a nickel; given a dollar, the machine outputs four quarters, and given a five-dollar bill, the machine outputs five one-dollar bills. How many times must Jenny use the change machine in order to convert a five-dollar bill into 500 pennies?

No Solution Yet Submitted by Danish Ahmed Khan

No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)

solution, maybe minimal

| Comment 1 of 2

Pennies from nickels from dimes and quarters from dollars from five-dollars.

One five dollar bill to five one-dollar bills. 1 use

Five one-dollar bills into twenty quarters. 5 uses

Twenty quarters into forty dimes and twenty nickels. 20 uses

Forty dimes into eighty nickels. 40 uses

That gives one hundred nickels total. Turning them into pennies one at a time. 100 uses

1+5+20+40+100=166 matchine uses

Posted by xdog on 2025-05-01 08:55:32

Please log in:

Login:
Password:
Remember me:

Sign up! \| Forgot password

Search:

Search body:

Forums (1)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info