Question 1:
The time taken, t in hour, to mow a lawn varies directly as the area of a field, L in m2, and inversely as the number of workers, w. Given that 5 workers need 3 hours to mow the grasses of the field with area of 4 × 104 m2.
(a) Find the equation that relate t in terms of L and w. [2 marks]
(b) Calculate the minimum number of workers needed to mow the grass of a field with area of 1.6 × 105 m2 within 8 hours. [2 marks]
Solution:
(a)
(b)
The time taken, t in hour, to mow a lawn varies directly as the area of a field, L in m2, and inversely as the number of workers, w. Given that 5 workers need 3 hours to mow the grasses of the field with area of 4 × 104 m2.
(a) Find the equation that relate t in terms of L and w. [2 marks]
(b) Calculate the minimum number of workers needed to mow the grass of a field with area of 1.6 × 105 m2 within 8 hours. [2 marks]
Solution:
(a)
(b)
Question 2:
Diagram 1 in the answer space shows a square PQRS drawn on a square grid with sides of 1 unit. Y is a point that move inside the square.
(a) On Diagram 1, draw the locus of point Y which always moves 3 units from point K. [1 mark]

(b) Calculate the distance travelled by locus Y in 2(a). [2 marks]
Solution:
(a)

(b)
Diagram 1 in the answer space shows a square PQRS drawn on a square grid with sides of 1 unit. Y is a point that move inside the square.
(a) On Diagram 1, draw the locus of point Y which always moves 3 units from point K. [1 mark]

(b) Calculate the distance travelled by locus Y in 2(a). [2 marks]
Solution:
(a)

(b)