Apencil and a ruler cost $1.50 together. the ruler costs $1.00 more than the pencil. how much does the pencil cost?

The pencil costs $0.25.

One way to deduce this is to divide 1.50 by 2 (equaling 0.75) and then subtracting .5 to get 0.25 because if it's $1 more, then the ruler would cost 0.75 + 0.5 and the pencil would cost 0.75 - 0.5, making a total of $1.50.

Another way is to make it an equation. Let's say the ruler is r dollars and the pencil is p dollars.
r + p = 1.50
r = p + 1.00
If we know these two equations, then you can substitute p + 1.00 in the 1st equation (instead of r). This gets us:
p + 1.00 + p = 1.50
You can simplify this into:
2p + 1.00 = 1.50
Then you subtract 1.00 from both sides:
2p = 0.50
And you divide 2 from both sides:
p = 0.25
Getting you the answer of:
The pencil costs $0.25

Hope this helps! :)