(b) For a musical show, x children were present. There were 60 more adults than children. An adult paid D5 and a child D2. If a total of D1280 was collected, calculate the
(i) value of x;
(ii) ratio of the number of children to the number of adults;
(iii) average amount paid per person;
(iv) percentage profit if the organizers spent D720 on the show.
Candidates’ performance in part (a) of the question was said to be satisfactory. They exhibited a good understanding of the theories of logarithms and were able to apply them correctly. They were able to express the figures in terms of 5, 7 and 8 thus: log () = log( ) which on applying the laws of logarithms gives 4log 7 = 4 x 0.8451 = 3.3804.
In the part (b), candidates’ performance was reportedly fair. A good number of them were able to get the equation 2x + 5(x + 60) = 1280. Solving it gave x = 140. The ratio was given by = 7:10. Average cost = = D3.76. The percentage profit = x 100 = 77.8%.
).
) = log( 
) which on applying the laws of logarithms gives 4log 7 = 4 x 0.8451 = 3.3804. 
= 7:10. Average cost = 
= D3.76. The percentage profit = 
x 100 = 77.8%.