Common Mistake Of Gaps and Length

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There are some maths questions that will be out to catch the careless learner.

A common one is that which require you to calculate the distance or length given the gap of items.

Look at the diagram below for an example.


Here, can you find the length from the left-most pillar to the 8th pillar, given the distance from start to 3rd pillar is 30m?

Solution: (Wrong slip-of-the-mind working)

Since the distance is 30m for 3rd pillar, answer to 8th pillar has to be 80m.

Seems to be right and logical. ==> Careful here!

Why?

Look at the step distance in between pillar. It is 30m / 2 = 15m.

As the gap between pillar from start to 8th pillar is only 7 gaps,
the actual correct distance is 7 x 15m = 105m.

Interestingly tricky question, right?
Be careful and alert for this "step" or "gap" maths problem.
Slamp down this carelessness, and mistake will eventually disappear (for this type).

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