DEVELOPING ESTIMATION SKILLS :  A study was done with some Class 3 and Class 4 children of five village schools to gauge how well they had understood the standard algorithms. The children were asked to solve problems of the type 1234 + 469. The responses were very interesting. Many of them were:

The children were; surprised by such answers. Clearly, their ability to estimate the approximate size of the answer was undeveloped. Therefore, they didn't ask themselves or, answer, "Does my answer seem reasonable?"

Why is this ability to estimate the computed result important? Don't we apply it again and again in our daily lives'? For instance, when we are buying several things, and want to quickly make sure that the total cost is within our budget, isn't this skill we use.

The ability to estimate computed results also helps us to detect arithmetical errors. Even when we use calculators, it helps us to quickly check if we haven't pressed any wrong buttons!.You can think of other ways in which this ability helps, while doing the following exercise.