Question 2

2.1.1 The total cost for Call package A is given by the following formula:
Total cost (in Rand) = R100 + number of minutes more than 100 x R0,80

(a) Write down a formula which can be used to calculate the
total cost in Rand for Call package B. (3)

(b) If Call package B is used, determine the total cost in Rand,
if Mr. Gardner and his family made calls with a total
duration of 625 minutes. (4)

2.1.2 The line graph illustrated in ANNEXURE B shows the total cost for
Call package B. On the same set of axes, draw a line graph to
illustrate the total cost for Call package A. (5)

2.1.3 Briefly define what is meant by concept, break-even point, in the
given context. (2)

2.1.4 Write down the co-ordinates of the break-even point on the graph. (2)

2.1.5 Show by means of calculation that Call Package A costs 20 cents
more than Call Package B for using the minimum number of
minutes after the break-even point. (4)

2.1.6 Mr. Gardner wants to spend a maximum of R300 per month on one
of the Call packages. Which Call package would you advise him to
choose? Motivate your answer by showing all calculations. (5)

2.2 The service providers have a major task on their hands. For Landline
numbers they have to use a system where they make entirely sure that a
number is not duplicated (repeated).

Landline numbers consists of ten digits. The first three digits are for the area
code followed by seven digits. The first three digits of the remaining seven
digits for the area where Mr. Gardner lives, starts with 423 followed by the
last four digits.

The last four digits are numbers that can be repeated using the numbers 0
to 9.

Show with calculations how many households in Mr. Gardner’s area can be
issued with a landline number starting with 041 423 _ _ _ _? (3)

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