Answer: Mr. Lim should plant at least 6 trees to have them placed the same distance from each other.
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Step-by-step explanation:
Mr. Lim wants to plant trees on every side of the rectangle-shaped garden. This means he needs to plant trees along the 24 meter length as well as the 18 meter width. Let's call the distance between each tree "d".
Along the length of the garden, there are 24 meters / d meters between each tree. This means there are (24/d) - 1 gaps between the trees where Mr. Lim won't be planting anything.
Along the width of the garden, there are 18 meters / d meters between each tree. This means there are (18/d) - 1 gaps between the trees where Mr. Lim won't be planting anything.
To minimize the number of trees, we want to choose a value of "d" that results in the fewest number of gaps along both dimensions. In other words, we want to find a value of "d" that will divide both (24/d) - 1 and (18/d) - 1 evenly.
Let's list out the factors of 24 and 18:
24: 1, 2, 3, 4, 6, 8, 12, 24
18: 1, 2, 3, 6, 9, 18
We can see that the only factor that both (24/d) - 1 and (18/d) - 1 have in common is 2. Let's try setting d = 12, which will give us two trees along the 24 meter length and one tree along the 18 meter width:
24 meters / 12 meters = 2 gaps between trees
18 meters / 12 meters = 1 gap between trees
This gives us a total of 2 + 2 + 1 + 1 = 6 trees.
Therefore, Mr. Lim should plant at least 6 trees to have them placed the same distance from each other.