ruler cost $12
Step-by-step explanation:
step 1
Let cost of ruler be represented as r
and cost of pencil be represented as p
we were given that
4 rulers and a pencil and these cost the same as 2 rulers and 4 pencils which is expressed as
4r + p = 2r+ 4p
and cost of pencil= $8
therefore
sTEP 2--- Solving
4r+ 8 = 2r+ 4 x8
4r+ 8 = 2r+ 32
4r - 2r= 32-8
2r= 24
r= 24/2 = r= $12