Current US Coins are limited to $1 so the number of coins to reach $19.95 will be 24. Nineteen $1 coins, three quarters and two dimes.
In times gone by, US currency included $10 and $5 coins so the number was once lower than the current 24 coins.
UK currency has a £2 coin so £19.95 will require 14 coins. Nine £2 coins, one £1 coin, one 50 pence, two 20 pence coins and a 5 pence coin.
A lot
A multiple of 11 can't be a prime number.
One
The smallest is 55.
If n is the number of nickels and d the number of dimes, then the equations are:n + d = 160 (total number of coins) 5n + 10d = 1050 (total value). And I have thought through to the answer.
Since the smallest of these currency values (the nickel) is equal to 5 cents, the number of five cent coins that go into a dollar is equal to 20. It is impossible to have a combination of 35 nickels and dimes whose sum is exactly equal to a dollar.
Assuming you're talking about English money... £2.00 x 8 £1.00 x 1 50p x 1 20p x 1 10p x 1 2p x 2 1p x 1 is a total of 15 coins
A lot
A multiple of 11 can't be a prime number.
One
The smallest is 55.
20 - 10 of each
You have provided insufficient information to answer the question. You would need to tell either (i) the total number of coins or (ii) the exact total value.
If n is the number of nickels and d the number of dimes, then the equations are:n + d = 160 (total number of coins) 5n + 10d = 1050 (total value). And I have thought through to the answer.
One estimate places to total number of coins in circulation at about 30 billion.
The smallest consecutive three numbers that total 120 are... 39, 40 & 41.
The smallest number is LCM(2, 3, 4, 5, 6) + 1 = 61