How to answer Section B (May 2012 example) YEAR 12 REVISION

Describe what is meant by simulation modelling. (1) Use of a program to predict the behaviour of a real life system.

Describe the advantages and disadvantages of using simulation modelling in car crash analysis. [3]  Cheaper as do not have to physically destroy cars  Safer as nobody is really hurt  Much more flexible  Can explore different scenarios more easily  Model could oversimplify the situation and not be accurate enough  Bad data errors in formulas will spoil accuracy  No model is ever 100% accurate

Describe the purpose or function of one formula from list A and two different formulas from list B, which you have used in your spreadsheet. [6] A: SUM, COUNT, MAX, MIN, AVERAGE, RAND B: Single IF, Multiple IF, DATE, ROUND - My Count formula on page 5, cell D24, counts the number of numbers in cell range A23 to D23 (1) This allows me to see how many different items I have in stock. I can then decide to try and add more items if there is not much choice(1) - I used the SUM function (SUM C2:C24) in column C of page 3 to add up all the costs of the different items the customer has ordered(1) to work out the total price(1). - I used the Min/Max function (Min/Max B2:B24) in column B of page 4 to find the cheapest/most expensive item I have in stock(1). This would allow me to compare the prices of my items and if needed amend them depending on their sales.

Describe the purpose or function of one formula from list A and two different formulas from list B, which you have used in your spreadsheet. [6] A: SUM, COUNT, MAX, MIN, AVERAGE, RAND B: Single IF, Multiple IF, DATE, ROUND ◦Single If, Page 5, cell A50. The Single If formula =if(A40=True, 0.2, 0) checks to see if someone is a returning customer. If they are a returning customer they receive a 20% discount. ◦Date, Page 4, cell B30. The date formula =date(B30,B29,B28) takes the input of 3 scroll bars and formats them into a date. This is then presented to the customer on their invoice in their invoice so they know when their order will arrive.

Describe the way you used a VLOOKUP function (or its variations) in your spreadsheet, giving one advantage and one disadvantage of using this function in your spreadsheet. [3] Example A Vlookup can be seen on page 13 cell D6 in the table on page 14. Once an item has been chosen, the price is found from the information I have already put in the stock table in the stock sheet. (1) AdvantageDisadvantage Reducing data entry errorsIf the item changes value then I will have to go and change the price sheet as well Increasing efficiency supported by a suitable example If you rename or move the table it will not work. If a price changes you only have to change it in the reference table Data has to be sorted into order (generally true) Speed of data entryIf there are errors in the look up table there will be errors in the result.

Describe one method of validation error trapping used in your spreadsheet. [3] In cell B3 on page 2, I put a range check of between 1 and 10 on my item number to ensure item codes were within the correct range In cell F12 on page 8, I set the text length between 4 and 8 characters to put a limit on customer Postcode to prevent incorrect data being entered Description of their own appropriate error message (1).

Describe a SORT used in your spreadsheet and state why you required the data to be sorted. [2] I sorted the names of my customers on page 13 as it made it a lot easier to look for people when their surnames were in alphabetic order. To make a list ready for Vlookup I sorted the prices of my stock items on page 16 as it made it a lot easier to look for items when their prices were in numerical order. To make a list ready for Vlookup

Describe a GRAPH used in your spreadsheet and the reason you put the data in the form of a graph. [2] I used a breakeven graph on page 12, in my profit loss graph, this allowed me to find the number of items I had to sell before I was going to start making a profit. Graph: The graph on page 8 shows me a graph of the items sold and it allowed me to see the most popular items.