Warren has exactly three types of coins in his piggy bank: $0.25, $0.50, and $1. If the number of $0.25 coins is 8, and the number of $0.50 coins is 4, how many $1 coins does he have?
(1) The total value of the $1 coins in the piggy bank is 50% of the total value of all the coins.
0.25*8= $2 and 0.50*4= $2, Let's assume, there are total 4 numbers of 1 dollar coins. Then, the value of all coins would be, 2+2+4=8 and the value of 1 dollar coin would be $4 which is 50% of the total value of all the coins.
So, (1) is sufficient to answer the question.
(2) The $1 coins make up 25% of the total number of coins in the piggy bank.
Let's assume, there are total 4 numbers of 1 dollar coins. Then, the number of all coins would be, 8+4+4=16, So, the number of 1 dollar coins in the bank would be 25% of the total number of coins.
So, (2) is sufficient to answer the question.
Answer: D.