Simon has 23 coins. Some are 5-cent coins and the rest are 10-cent coins. The total value of the coins is $1.60. How many 5-cent coins does he have?
Simon has 23 coins. Some are 5-cent coins and the rest are 10-cent coins. The total value of the coins is $1.60. How many 5-cent coins does he have?
Let x be the number of 5-cent coins and y be the number of 10-cent coins.
We know that x + y = 23 and 0.05x + 0.1y = $1.60.
We can solve the first equation for x: x = 23 - y.
Substituting this into the second equation, we get 0.05(23 - y) + 0.1y = $1.60.
Expanding the equation, we get 1.15 - 0.05y + 0.1y = $1.60.
Combining like terms, we get 0.05y = $0.45.
Dividing both sides by 0.05, we get y = 9.
Substituting this value back into x = 23 - y, we get x = 23 - 9 = 14.
Simon has 14 5-cent coins. Answer: \boxed{14}.