Question

A pen and its ink refill together cost $\;\$1.10$. The pen costs $\;\$1$ more than the ink refill. What is the cost of the pen in dollars?

Answer 1

$1.05

Explanation:

Let the cost of ink refill be $x

given

The pen costs 1$ more than the ink refill

Then, cost of pen in terms of x is $( x + 1)

Total cost of pen and refill in terms of x = x + x+ 1 = 2x + 1

It is also given

A pen and its ink refill together cost $\;\$1.10$

Thus,

2x + 1 = 1.10

=> 2x = 1.10 - 1 = 0.1

=> x = 0.1/2 = 0.05

Thus, cost of refill = $0.05

cost of pen = 1+ x = 1 + 0.05 = 1.05

Thus, cost of pen in $ is 1.05.