In the first expression, you move the decimal point to the right 8 times, due to the negative exponent, giving you 0.0000000413. The second expression requires you to move the decimal point to the left 5 times, because of the positve exponent, giving you 4000. You then divide these products, giving you the very small number of 1.0325e-11, or 0.000000000010325.