You went to a store to buy a baseball and bat.  It cost $1.10.  If the bat cost $1 more than the ball, how much did the ball cost?

Wouldn't you want two? 

price of ball = x
price of bat = y
 
so
 
$1.10 = x + y
 
if the price of the bat is $1.00 more than the price of the ball we can say:
 
y = ($1.00 + x) 
 
substitute into the above equation to get it all in terms of the same variable:
 
$1.10 = x + ($1.00 + x) = $1.00 + 2x
 
subtract $1.00 from both sides of the equation and solve for x
 
$0.10 = 2x
x = $0.05
 
so, if I am interpreting your question correctly, the bat is $1.05 and the ball is $0.05.

quantumeffect beat me to it but I just went, for b = bat: 
 
b + (b-100) = 110
2b - 100 = 110
2b = 210
b = 105

Therefore bat is $1.05 and ball is $0.05

This is a quiz used by psychologists.  People who stereotype and work on the quick-to-judge thoughts will almost always first say 10 cents.  Try it on your friends.

Don't you just hate it when you're tricked into taking psychological tests 

Kanye says both items are 50 cents 'cause Rap is the genre of geeniousses.

FWIW, I almost replied with 10 cents just to make you feel good about yourself. 
 

eph221
Try it on your friends.

Yer my only friend and you know the answer.