Lamp posts were located at an equal distance of 9 m apart from one another, starting from the beginning of the road. Between every 2 lamp posts, there were 2 plants, planted 3 m apart.
- What was the distance between the first plant and the 6th plant?
- What was the distance between the fourth plant and the tenth plant?
- Given that the stretch of road was 63 m, how many plants were there?
Lamp post ↔ plant ↔ plant ↔ Lamp post ↔ plant ↔ plant ↔ Lamp post ↔ plant ↔ plant ↔ Lamp post
(a)
Length of each gap
= 9 ÷ 3
= 3
Distance between first and 6th plant
= 7 intervals
= 7 x 3
= 21 m
(b)
Distance between fourth and tenth plant
= 9 intervals
= 9 x 3
= 27 m
(c)
Distance between 2 lamp posts = 9 m
Number of sets of 9 m
= 63 ÷ 9
= 7
Number of plants
= 7 x 2
= 14
Answer(s): (a) 21 m; (b) 27 m; (c) 14