What is the mean absolute deviation of the following set of data?

12 10 12 6 8 4 2 12

Astore sells two types of radios. one type sells $87 and the other for $119. if 25 were sold and the sales were $2495, how many of the $87 radios were sold a) 5 b) 20 c) 15 d)10

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?