
(b) Calculate the size of an interior angle of a regular nonagon.
6. The number of square tiles needed to surface the floor of a hall varies inversely as the square of
the length of a side of the tile used. If 2016 tiles of side 0.4m would be needed to surface the floor
of a certain hall, how many tiles of side 0.3m would be required?
7. The ratio of men : women : children living in Mkuza village is 6 : 7 : 3. If there are 42,000 women, find
how many:
(a) (i)children live in Mkuza village
(ii) people altogether live in Mkuza village.
(b) The 42,000 women is an increase of 20% on the number of women 10 years ago. How many
women lived in the village?
8. (a) If the first term of an arithmetic progression is 3 and the third term is 13, find the second term, the
fourth term and the sum of the first ten terms.
(b) A certain geometric progression has a common ratio of 2 and the sum of the first five terms is
155. Find the first term and give the formula for the n
th
term.
9. Figure 2 represents plotting of two stations A and B which are 4,000m apart. T is a stationary target in
the same vertical plane as A and B . When the distance from station A is 10,000m, the angle of
elevation is 30°. Calculate
(a) The vertical height of the target, T X
(b) The distance AX , BX and T B
(c) The angle of elevation of the target, T , from B
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