Learning to make change with the least number of coins is useful in the real world.
For example, if a cashier needs to give you 25 cents in change, would you rather have 25 pennies or 1 quarter?
It is easier to carry around 1 quarter than 25 pennies.

Example 1: Least number of coins

Calculate the correct amount of change.
How do you make 30 cents in change using the least number of coins?

We start with the largest coin, the quarter, which is worth 25 cents.

Q: How many quarters go into 30 cents?
A: 1
30 cents - (1 × 25 cents) = 5 cents

Now, we need find how to make 5 cents in change with the least number of coins.
We go to the next largest coin, the dime, which is worth 10 cents.

Q: How many dimes go into 5 cents?
A: 0

We go to the next largest coin, the nickel, which is worth 5 cents.

Q: How many nickels go into 5 cents?
A: 1
5 cents - (1 × 5 cents) = 0

So, 30 cents = 1 quarter + 1 nickel

The answer is         

Example 2: Least number of coins

Calculate the correct amount of change.
How do you make 92 cents in change using the least number of coins?

We start with the largest coin, the quarter, which is worth 25 cents.

Q: How many quarters go into 92 cents?
A: 3
92 cents - (3 × 25 cents) = 92 cents - 75 cents = 17 cents

Now, we need find how to make 17 cents in change with the least number of coins.
We go to the next largest coin, the dime, which is worth 10 cents.

Q: How many dimes go into 17 cents?
A: 1
17 cents - (1 × 10 cents) = 7 cents

Now, we need find how to make 7 cents in change with the least number of coins.
We go to the next largest coin, the nickel, which is worth 5 cents.

Q: How many nickels go into 5 cents?
A: 1
7 cents - (1 × 5 cents) = 2 cents

Now, we need find how to make 2 cents in change with the least number of coins.
We go to the next largest coin, the penny, which is worth 1 cent.

Q: How many pennies go into 2 cents?
A: 2
2 cents - (2 × 1 cents) = 0

So, 92 cents = 3 quarters + 1 dime + 1 nickel + 2 pennies

The answer is