Each of the following shapes has a value:

 $= 7$ $= 17$ $= \; ?$

The value of the circle changes in each of the following problems.
Can you discover its value in each problem, if the value of the shapes are being added together?

 (a) $= 25$ (b) $= 51$ (c) $=136$ (d) $=48$ (e) $=100$

You could print off this sheet of the problem.