X + 9y = 8 x − 4y = –18

Which function is increasing? o a. f(x)=(1/15)* o b. f(x)= (0.5)* o c. f(x)=(1/5)* o d. f(x) = 5*

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

How can you find the mean absolute deviation (mad) for this set of data?