Answer:
Most people found the probability of just stopping at the first light and the probability of just stopping at the second light and added them together. I'm just going to show another valid way to solve this problem. You can solve these kinds of problems whichever way you prefer.
There are three possibilities we need to consider:
Being stopped at both lights
Being stopped at neither light
Being stopped at exactly one light
The sum of the probabilities of all of the events has to be 1 because there is a 100% chance that one of these possibilities has to occur, so the probability of being stopped at exactly one light is 1 minus the probability of being stopped at both lights minus the probability of being stopped at neither.
Because the lights are independent, the probability of being stopped at both lights is just the probability of being stopped at the first light times the probability of being stopped at the second light. (0.4)(0.7) = 0.28
The probability of being stopped at neither is the probability of not being stopped at the first light, which is 1-0.4 or 0.6, times the probability of not being stopped at the second light, which is 1-0.7 or 0.3. (0.6)(0.3) = 0.18
Step-by-step explanation:
The answer to 1 is (E) All of the above. This is because a negative cannot be under a square root and it comes out as an i.
The answer to 2 is (B) a is real and b is imaginary. This is because anything that has an "i" attached to it is considered imaginary.
Do you mean 3.14 for pi or just 3?
Ok so a triangle is equal to 180 degrees!!!
So with that info u can make a crazy little equation
180=70+68+47+x
Ok then you add 70,68 and 47
180=185+x
Ok now u have to subtract 185 on both sides
And get the answer -5=x or x=-5 (same thing)
