The probability of an event is given by the number of favorable outcomes divided by the total number of outcomes. Here the event is the alarm clock running out of power. There are 24 hours during which the power can go out. You are asleep during 8 of these. A "favorable" outcome in this case is the power going out while you are sleeping -- that is, during one of those 8 hours. This makes the probability that the power goes out while you are sleeping 8/24.
Answer:
4
Step-by-step explanation:
first you simplify, so -1-3=-4.
|-4|
the absolute value of negative four is just four with all signs removed (in this case, negative sign)
4
Answer
4.25
Step-by-step explanation:
She would have baby sat for 4 hours and 15 minutes.
the 15 minutes comes in when we have the .25 because 1/4 of an hour is 15 minutes.
we can check this if we do 38.25 divided by 4.25 and we get 9.
The appropriate choice is z = 1.41.
The empirical rule tells you 68% of the distribution is within 1 standard deviation, so p(z > 1) ≈ 0.17. This means the z value is more than 1 for the probability to drop to 0.08. The only choice that is greater than 1 is 1.41. (The number is actually about 1.40507.)