The following data relating to units shipped and total shipping expense have been assembled by YORK, a wholesaler of large, custom-built air-conditioning units for commercial buildings: (5-Marks)

Month ....... Total Shipped units ...... Shipping Expenses

1 January ...........9....................................... $ 4,500

2 February .........18....................................... $ 5,750

3 March ..............12 .......................................$ 4,250

4 April ................15....................................... $ 5,000

5 May .................21....................................... $ 5,750

6 June .................24....................................... $ 6,750

7 July ....................6 ........................................$ 3,000

a. Use the high-low method to find the cost formula for shipping expense :

• Shipping Expenses =

b. Use the regression method (Graph x/y) to find the cost formula for shipping expense :

• Shipping Expenses =

c. Estimate the total cost in the next month if the number of shipped units is expected to be 11

• Using High-Low Method:
• Using Regression analysis (Graph X/Y):