Three. A 20 cent, 10 cent and 5 cent coin.
Using standard American coins (1, 5, 10, 25 cents), the fewest number of coins to make $0.13 would be four -- one dime and three pennies. This number would be different in countries that use different denomination coins, such as the 2-cent piece.
Four current American coins
One 50-cent coin, two 10-cent coins, and two 1-cent coins.
Simple answer: 98 coins of 1 cent each.
One way of doing this is with 19 ten-cent coins and 10 one-cent coins.
50 two cent coins, they exist.
25 cent and 10 cent and 1 cent
Cent cent cent cent cent nickel nickel nickel nickel ....,.., not possible
Three coins; 50, 25, and 1.
Just one, a dime.
With US coins, a half-dollar and two nickels, or two quarters and a dime. If you have 20-cent coins, 3 of those, or the 50 cent and two 5 cent coins.
a dime, a quarter and a fifty-cent piece.
20 cent coins
Two in many countries: 0.25 and 0.10.
There is no straightforward answer, you can make it with 50 or 45 coins quite easily if you use 50 one-cent coins or 49 one-cent coins and a 5-cent coin. You could bend the meaning of the question using non-US currencies, or by trading, etc.
Three dimes 30 one-cent coins A quarter and 5 one-cent coins