Lyman company returned $750 of goods it had purchased from another company. the original invoice was for $4,200, 3/10, n/30. what is the discount if lyman pays the balance within the discount period?

Calculation: 
3/10                3>3% discount     
                      10>the days in the discount period, the company has 10 days to pay the bill in full. 

Therefore

Lyman pays the balance within the discount period

 ($4,200 – $750) x .03 = $103.50

the discount is $103.50

The length is 23 and y because you add them together