The probability that will not rain today is: 85%
100% - 15% = 85%
The correct answer is A
The probability of an event cannot be less than 0 because 0 means it's impossible. The probability of an event cannot be more than 1 because 1 means that it's certain that it will happen. That's why the probability must be between 0 and 1.
The answer is 5 and 0
(-5) + 5 = 0
Convert the two fractions into simpler fractions: 3 2/5 --> 17/5 and 4 1/5 --> 21/5. Notice the the denominators are identical, so we simply add the numerators: (17 + 21)/5 = 38/5 = 7 3/5.
There is an easier way to do this, this is just the most clear way of seeing everything.
