ECZ 2012 · O-Level Paper 2 · Question 11 — Linear Programming

Question from ECZ 2012 · O-Level Paper 2 · Question 11

(a) The graph below shows three inequalities that satisfy Kashita's intentions to purchase Science and Mathematics text books.

Diagram for part (a)

(a(i)) Given that x represents the number of Science text books and y represents Mathematics text books, write the three inequalities that represent the unshaded region R.[4]

Verified working — step 1

The vertical line is x = 5, shaded to its left: x ≥ 5.

(a(ii)) Given that a Science textbook costs K25 000 and a Mathematics textbook K10 000, find the largest number of Science and Mathematics textbooks that can be bought. Hence calculate the total cost of the textbooks.[3]

Verified working — step 1

The question asks for the largest NUMBER of books, so maximise x + y.

(b) A box has 7 identical sweets. 3 of these are green and the rest are red. Kamwanga picks one sweet at random and eats it. After sometime, he picks another one and eats it.

(b(i)) Construct a tree diagram to illustrate the outcomes of the two sweets taken.[3]

Verified working — step 1

7 sweets at the first pick, and only 6 at the second since none is replaced.

(b(ii)) Calculate the probability that the first sweet was red and the second was green.[2]

Verified working — step 1

This asks for one specific ORDER: red first, then green.

The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.

Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.

Have a different question?

Search it — if it is from a past paper or a school mock, chances are we have it worked out, or one that uses the same method.

Search any past-paper question

More Linear Programming questions from past papers