June 15 question 1

Hi,

I am sure this is very straight forward but for some I can not get my head round it. Question 1 part ii, please can you help explain the break even calculation. Response 1 says that costs will increase by 10% however in the answer it increases the number of shoes brought by 10% and not the $21 per unit. I would I have increased the cost per unit by the 10%.

Please can you also explain how the new contribution per unit at 51.9 is calculated as well.

Thanks much appreciated.

N