To find the number of quarters in a stack one foot high, I need to convert the units to inches, since that is how the quarters are measured. One foot is equivalent to 12 inches, so I can write that as 12 in. I also need to find the thickness of one quarter, since that will help me determine how many quarters fit in a given height. To find the thickness of one quarter, I can divide the total thickness of the stack by the number of quarters in it. The total thickness of the stack is half an inch, which I can write as 0.5 in. The number of quarters in the stack is eight, so I can write that as 8. To find the thickness of one quarter, I can divide 0.5 in by 8, which gives me 0.0625 in. This means that one quarter is 0.0625 inches thick. Now I can use this to find the number of quarters in a stack 12 inches high. To do this, I can divide the total height of the stack by the thickness of one quarter. That is, I can divide 12 in by 0.0625 in, which gives me 192. This means that I need 192 quarters to make a stack one foot high. 
If a stack of eight quarters is exactly half an inch, how many quarters will be needed to make a stack one foot high?