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Question
primary 5 | Maths
| Whole Numbers
One Answer Below
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Finding the length of the walkway
Therefore, 5X = 3(X + 60)
Expand:
5X = 3X + 180
Subtract 3X on both sides:
2X = 180
Simplify:
X = 90
Therefore, the walkway was 5m * 90 = 450m.
Hence, the number of 2m planks needed to make the walkway is 450m / 2m = 225.
See 1 Answer
You must notice that three 5m planks have the same length as five 3m planks. This means that you need two extra planks to cover that same distance of 15m.
Since you need 60 extra planks to cover the walkway,
2 units --> 15m
60 units --> 15 x 60 / 2 = 450 m.