Hi,

You did not provide values that variables contain, but according to the checkpoint's screenshot, it is my guess that variables contain not numeric values, but some string values (currency symbol with the number).

If my guess is correct, then you should do the following:

-- Parse the value to be stored to the variable and strip everything except numeric value;

-- Set the project variable to be of double type;

-- Assign the value to the variable;

-- Repeat the above with the second value and variable;

-- Now values of project variables can be summed.

Note, that as you are totaling float values, the result might be not exact expected value but expected value plus/minus some delta caused by rounding. This is a usual problem for the mathematical operations over float numbers.