What is the mean absolute deviation of the following set of data? 2 20 4 16 10 12 8 4

Which expression is equivalent to sq-80

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?