9- (-4) =
14 -9 =
(-4) - (-5) =
-7 - 9 =

In the geometric progression –3, 12, −48… what term is 3,072?

If tan2a=cot(a+60), find the value of a, where 2a is an acute angle

Television viewing reached a new high when the global information and measurement company reported a mean daily viewing time of 8.35 hours per household. use a normal probability distribution with a standard deviation of 2.5 hours to answer the following questions about daily television viewing per household. a. what is the probability that a household views television between 4 and 10 hours a day? (to 4 decimals) b. how many hours of television viewing must a household have in order to be in the top 7% of all television viewing household? (to 2 decimals) c. what is the probability that a household views television more than 4 hours a day? (to 4 decimals)