Step 1:  Use question 1 of our previous quiz to create a multiple choice question.

                    What is 5% of 80?            (Answer: 4)

a. We know we need 3 variables for the question and the solution.

   1. “p” – percentage,    2.   “a” – first value   and    3. “b” –  percentage value

We will also need 4 variables for the multiple choice answers.

       We'll use:  “AnsA”, “AnsB”, “AnsC” and “AnsD”.

b. As before, the correct answer to this question is: b=a*p/100  . So we will set AnsA = b.

     What are three typical mistakes students might make?

1. Students might forget to divide by 100, so we will set AnsB = ap.
2. Students might confuse the roles of a and b,so we will set AnsC = a*100/p  .
3. Students might just be too lazy to multiply and look for a logical answer, so we give a choice close to the correct answer: AnsD =a*(p+5)/100 .  

c. What range of values do we want for our variables?

1. p between 1% and 300% (allow for one decimal).
2. a and b between 0.1 and 999.9 (allow for one decimal).

d. Do we have any other conditions?

We will round a, p, and b to the nearest tenth.

We want a, p, and b to be unique for all questions in our quiz.

Now we're ready to create the question.

Step 2: Create the basic variables -(see Chapter 1, Part C, Step 2 for more explanation).

•    Open the variable list with [Ctrl] +[D] or select the Edit menu and then Algorithm Definitions.
•    In the Edit Algorithm Definitions, click on New.

The New Algorithm dialog box will open and the cursor will be in the Variable name field.

   1. Type the letter “a”, press [Tab].  (The cursor will move to the Definition field.)

   2. Type “range(.1,999.9,.1).

With this definition, EVTG will generate values for a starting with .1 and increasing by increments of .1 up to the value 999.9  (.1, .2, .3, .4, .5, .6, .7, .8, .9, 1, ... ,999.9)

   3. Click on the down arrow right of “General” in the Format field and then

 

   4. click on “Number”.

 

Two new fields will open, namely: Decimal places and Fixed .

5. Click on the down arrow right of “0” Decimal places and then

6. click on “1”.

7. Click on the box in front of “Make only...” to select it.

8. Click on OK to save the variable.

Now, we define the variable p.

• Click on New and then work as in picture below.

We define our third variable b. 

• Click on New and then work as in picture below.

Step 3: Create the answer variables.

Notice that we do not click “Make only this variable value...”  That is because we do not care whether different questions have the same answers.  We make a, p, and b unique because we want the questions to be different.

Here are the variable definitions for AnsB, AnsC and AnsD:

Step 4: Think about the conditions.

Very important:

We need each of our answers to be different.  EVTG will not check this for us!

Further, suppose AnsA=1.11 and AnsB=1.12.  EVTG considers these to be different even though when displayed with one decimal they will both be 1.1!

So, we must be very careful in setting our conditions.

Our suggestion is that we go back into the definitions of AnsA, AnsB, AnsC and AnsD and add the EVTG predefined special function round( ) around our definitions in the format round(...,1).  This ensures that each of answers is calculated to exactly one decimal place.

Then we add the uniqueness condition using the EVTG  predefined special function isunique( ): 

            isunique(AnsA,AnsB,AnsC,AnsD).

Step 5: Edit algorithm definitions.

• Click on AnsA in the Edit Algorithm Definitions box, then click on Edit
• (or just double-click on AnsA).

• Edit AnsB, AnsC and AnsD in the same way:

Step 6: Set the conditions.

Now, we add our condition that all of our answers are different.  We will be using this condition over and over, and we will copy it from one question to another.

• Click on New (in the Edit Algorithm Definitions box).

We add our condition to control the range of b.

• Click on New (in the Edit Algorithm Definitions box).

•    Click on Done to exit Edit Algorithm Definitions.

Here is the list of algorithm definitions:

Step 7: Write the question.

• Write the question and fill in the answers.  Remember that every variable must be inserted (select the Insert menu and then Variable; an inserted variable has a gray background).
• Don't forget to click the circle in front of a.

• Click on Record.

Below is our question.  Remember, your values will likely be different since EVTG generates the values randomly, according to our definitions.

Step 8: Save the file.

• Press [Ctrl]+[S] or click on the File menu, then on Save.
• In the Save dialog box, type the File name: Percentage Problems 1.
• Click on Save (or hit Enter).  The file name should now appear in the title bar.