Two friends want to buy a snack. They combine their money and find they have $3.80, consisting of quarters, dimes, and nickels. If they have 34 coins and the number of quarters is half the number of nickels, how many quarters do they have?  Pick:
A) 7
B) 8
C) 9
D) 10
E) 11
Let x be the number of quarters. Then 2x is the number of nickels.   (1) 25x + 10x + 10D = 380. Then 7x + 2D = 76   (2) 3x + D = 34. Then 6x + 2D = 68   Let's subtract equation (2) from equation (1).   x = 8   The answer is 8.
<result>B</result>
Two friends want to buy a snack. They combine their money and find they have $3.80, consisting of quarters, dimes, and nickels. If they have 34 coins and the number of quarters is half the number of nickels, how many quarters do they have?