In maths, we do come across topics on estimation.
This topics relate to our daily living very closely and is truly practical.
Example is when we go shopping and starts to count the expenses to be paid.
But mathematical estimation has one key concern.
To what extent or how accurate does one wish to?
There is no right or wrong to an answer when dealing with estimation. After all it is an ESTIMATED answer.
The basic requirement is thus to get as close to the true answer as possible.
Let's start with one simple example to demonstrate the concept.
y = 0.501 + square root(3.89)
What is y without using calculator ?
y = 1 + square root (4)
y = 1 + 2 = 3
y = 0.5 + square root (4)
y = 0.5 + 2 = 2.5
You can now see that both answers is close to the actual answer of 2.4733.
However, it is the gap or extent of the difference you wish for.
If possible, LOOK carefully at the numbers and give a best estimation closest to ability to compute the answer.
Here, from the above, you will notice the first term of 0.501 decides the outcome.
Estimate this 0.501 to what numeric value?
Think further and you will find that 0.501 to 1 will give you a bigger difference compared to 0.501 to 0.5.
If you can mentally handle 0.5 as the estimated value for computation, go for it since this should be closer to the final outcome.
Thus in conclusion, do look a bit closer to the numbers presented in your problem and simply do a brief calculation of the differences between estimated and raw data. Then you are one step closer to getting a good estimation.
Estimation, finally, boils down to how far you are to the actual answer. Nothing difficult.
Interesting? Any more suggestions?