Need Some Help Please

1.

[ Sarah's point total -  17 ]

____________________     =    2.8       multiply  both sides by 4

           4

Sarah's point total  -   17 =     11.2        add 17 to both sides

Sarah's point total   =    28.2

2.  A z-score of  2.8 means that she scored more points than about  99.74%  of  the participants.....this would be  considered very unusual