A student bought 3 notebooks and 1 pen for N35. After misplacing these items, she…

A student bought 3 notebooks and 1 pen for N35. After misplacing these items, she again bought 2 notebooks and 2 pens, all of the same type for
N30. What is the cost of a pen?

Correct Answer: Option A

Explanation

Represent notebook with x
Represent pen with y
∴ 3x+y=35 — (i)
2x+2y=30 — (ii)
Multiply eqn (i) by 2 and eqn (ii) by 1
6x+2y=70 — (iii)
2x+2y=30 — (iv)
Subtract eqn (iv) from eqn (iii)
4x = 40
X = 10
Substitute x = 10 in eqn (i)
3x+y=35
3(10)+y=35
Y = 5
∴ The cost of pen is N5.00