 # Chapter 3

### Chapter 3

Hi there,

I just have a range of questions in relations to the Chapter 3 from the Maths Section.

1. How do you get the answer for Question 2 without the use of a calculator?
2. How do you get the answer of 3 for Question 7? I have looked at the worked solutions and am still slightly confused?
3. In relation to Question 12, why is In (1) in the question stem? How do you determine the answer being 9 without the use of a calculator?
4. In relation to Question 15, I have looked at the worked solutions however am still confused as to determine that the answer is B. I thought that it may have been -In [A] as per the axis labels?

Thank you so much,

Kind regards and best wishes,

Em Stevens
emstevens46670

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### Re: Chapter 3

emstevens46670 wrote:
1. How do you get the answer for Question 2 without the use of a calculator?

Question 2 has only 2 very basic manipulations:

1) 13/39 = 1/3, which you do by asking: How many times does 13 go into 39, which is 3.

2) 3 x 9 = 27
goldstanda3269

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Joined: Wed Aug 25, 2010 10:59 pm

### Re: Chapter 3

emstevens46670 wrote:2. How do you get the answer of 3 for Question 7? I have looked at the worked solutions and am still slightly confused?

Please consider looking at the cross references (GM 3.3.1, etc) from the worked solution to remind yourself of the procedure for 2 equations. Then, please ask a question which lets us know which step of the worked solution is not clear to you and we will be happy to respond.
goldstanda3269

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Joined: Wed Aug 25, 2010 10:59 pm

### Re: Chapter 3

emstevens46670 wrote:3. In relation to Question 12, why is In (1) in the question stem? How do you determine the answer being 9 without the use of a calculator?

The question is answered by using the rules of logs and, definitely, without a calculator.

All the rules and examples are in GM 3.7.

The first term in the expression is: ln(e)^3 = 3, because that is the exponent (this was an example on page GM-100). ln is the natural log base e.

Just a reminder, log base 10 of 10 squared is 2, of 10 cubed is 3, of 10 to the power of 4 is 4. If the base and the number which is raised to a power is the same then the answer is the superscript.

Of course, ln(1) is in the question stem and any log of 1 is equal to zero. That is in the log rules and so it appears as 0 in the worked solution.

Consider having a look at the worked solution again to see if it is more clear.
goldstanda3269

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Joined: Wed Aug 25, 2010 10:59 pm