Q. On one side of a 1.01 km long road, 101 plants are planted at equal distance from each other. What is the total distance between 5 consecutive plants?
a. 40 m
b. 40.4 m
c. 50 m
d. 50.5 m
Correct Answer: b. 40.4 m
Question from UPSC Prelims 2022 CSAT Paper
Explanation :
101 plants on a 1.01 km road
Let’s say we have a road that is 1.01 km long. On one side of the road, there are 101 plants planted at equal distances from each other. We can convert the length of the road to meters: 1.01 km * 1000 m/km = 1010 m.
Now, imagine that the plants are represented by dots on a number line. The first plant is at position 0 and the last plant is at position 1010. Since there are 101 plants in total, there must be 100 gaps between them.
We can find the distance between two consecutive plants by dividing the total distance (1010 m) by the number of gaps (100): 1010 m / 100 = 10.1 m.
So, if we want to find the total distance between five consecutive plants, we need to multiply this distance (10.1 m) by one less than the number of plants because for 5 Consecutive Plants, gaps between them is 4 (5-1=4): 10.1 m * 4 = 40.4 m.