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WELCOME TO THIS PAGE INTENDED FOR STUDENTS AT THE UNIVERSITY OF THE WESTERN CAPE REGISTERED IN 2011  FOR THE MODULE

                                             QSF  132

T1 W4 L1

 

1.     THURS : TUT GROUP 16 : SEM 1 E

2.     THIS WEEK : TUTORIALS : A7 , A8

3.     CLASS TEST  THURS 4 AUG : TUT TEST 1, VAT, POPULATION, 2-1?

4.     TUTORIALS :  SWOPPING AROUND / CAMY

 

1. SIMILAR TO ‘HAMMERING’ PROBEM

A ‘devious’ assistant accountant  named Judas  ‘misappropriates’ 1 rand on day one, 2 rands on day two, etc, that is, one rand  more every day during the first five years of his employment. Assuming that each year has 365 days, how much money will Judas have misappropriated after five years?

2. SIMILAR TO ROSE TREES PROBLEM

A large company has to erect a number of wind turbines, each with rotor blade size of 7 metres, on a rectangular piece of suitable agricultural land. Each wind turbine has to be positioned at least 5 times the size of one rotor blade from each other.

21.             What is the maximum number of turbines that can be erected on the land    which is 2.03 km long and 1.26 km wide?

2.2      If each turbine costs 0.5 million rand to erect, what is the total cost to erect the maximum number of turbines on this land?

3. CALCULATOR SKILLS

4  NO CALCULATOR!!!

Calculate:

4.1         0.6  0.7 – 0.6  (–0.3 + 0.2)              

 

 

 

4.2       

5.  BRILLIANT STUDENT SOLUTION

 

If three men can dig five graves in 2 days, how long will seven men take to dig 50 graves?

 

 

 

METHOD 1: SIMPLER, but harder to understand.

 Since 7 men will do the job faster, multiply by the fraction

But 50 graves will take longer, thus multiply by the fraction

                   They will take

 

 

 

 

 

METHOD 2:  LONGER, but easier to understand – A simply brilliant student solution!

FIRSTLY, take the 5 graves and divide it by 2 days used to dig it. This gives us 2.5 graves per day.

SECONDLY, divide the 2.5 graves by the 3 men who dug the graves to get  days , which represents how much 1 man can dig in 1 day.

 THIRDLY, multiply 1 man by 7, since 7 men will be digging 50 graves. Therefore,  represents the number of 5.83 we divide graves per day.

 

FINALLY, we divide the 50 graves needed to be dug, by the 5.83 graves the 7 men can dig in one day. This gives us 8.57 days needed to dig the 50 graves.

 

 

 

 

©  DESMOND DESAI, DMD EDU-HOME, 2011

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