Solve the inequality state the solution 
set in interval notation and sketch its graph

                 <  - w < 


Clear of fractions by multiplying all terms on 
all three sides by the LCD of 15

         15 < 15 - 15w < 15

                  -9 < 3 - 2w < -5

Solve for w in the middle:  Add -3 to all three sides:

                  -9 < 3 - 2w < -5
                  -3  -3        -3
                --------------------
                 -12 <    -2w < -8

Divide all three sides by the coefficient of w, which is -2.
Remember that dividing through an inequality by a negative
causes the inequality symbols to switch directions:

                  >  > 

or simplifying:

                            6 > w > 4   <-----solution
  
which is the same as

                            4 < w < 6   <-----solution

whose number line graph is

       -------------------o=====o---------------   <-----graph
       -2 -1  0  1  2  3  4  5  6  7  8  9 10 11 

The interval notation is an abbreviation for that graph:

                              (4, 6)   <-----solution in interval       
                                                       notation
Edwin