Answer:
You bought 28 pencils and 2 pens.
Step-by-step explanation:
Define the following variables
X: Number of pencils bought
Y: Number of pens bought
Following the problem statement we have
X + Y = 30 we bought 30 pencils and pens (1)
0.25X +2Y = 11 Total cost of purchases (2)
We may solve this system using substitution. In Eq 1
Y = 30 -X (3)
Replacing (3) in (2)
0.25X +2(30-X) = 11
0.25 X + 60 -2X =11
60-11 = 2X-0.25X
49 = 1.75 X
X = 28 Pencils (4)
(4) in (3)
Y = 30 - 28 = 2
