To calculate expected value,
We can add up the probability of all possible events.
The 2 possible events are either winning $50 or losing the prize, which is $ - 50
Expected value =
50 x 40 % + (-50) x 60%
= $-10
So the answer is $-10
The scientific notation of the given, 35,000,000 is 3.5 x 10^7. The order of magnitude of a scientific notation is the exponent of its multiplier, 10. From the derived scientific notation above, the exponent of 10 is 7. Thus, the answer is letter D.
