How do I find RS? I've been having great trouble with questions like this recently.

RS = 5

To find the value of RS, you first have to solve for the variable x.

To do this you solve the equation of 2x - 6 + 1 + x - 4 = 18. You get this equation by adding all the values of the line PS together, equaling them to 18, because these lines have the same value.

Solving this equation gives you x = 9.

You then substitute 9 into x - 4.

9 - 4 = 5.

This gives you RS = 5

M< 5 = 80 , < 2 = 80, < 6= 100, < 3= 100, < 7= 80, < 4= 80, < 8= 100

How many groups are there?