Cost of pen = 20x when x< 10
and
=10x when x>10
Let the number of pens bought be x.
So the total pen cost is 20x when the number of the pen is less than 10.
Now let's take that the number of pens bought is more than 10
So the pen will cost a 50% discount
50% of 20x
= 20/100 × 20x
= 10x
So the cost of the pen will be 10x when the number of the pen is greater than 10.
From this, we get to know that
Cost of pen = 20x when x<10
and
= 10x when x>10
To know more about the cost and prices refer to the link given below:
https://brainly.com/question/28280938
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