Estimate -
2149 × 493 =
2149 round off to = 2100
493 round off to = 500
The estimated product = 2100 × 500
= 1,050,000

Estimating 2149 x 493

When we are asked to estimate a multiplication problem, it means we are not expected to find the exact result but an approximate value that can be easily calculated mentally. To estimate 2149 x 493, we can use rounding, compatible numbers, and other strategies.

Strategy 1: Rounding

One way to estimate multiplication is to round the factors to the nearest ten, hundred, or thousand, and then multiply them mentally. For example, we can round 2149 to 2100 and 493 to 500, and then multiply them as follows:

2100 x 500 = 1,050,000

This gives us an estimation of 2149 x 493 as around 1,050,000. However, we should keep in mind that rounding can introduce errors and that our estimation may not be very accurate.

Strategy 2: Compatible Numbers

Another way to estimate multiplication is to look for compatible numbers, which are numbers that are easy to multiply mentally because they have special properties. For example, we can notice that 493 is close to 500, which is a multiple of 10, and that 2149 is close to 2000, which is a multiple of 100. Therefore, we can rewrite the problem as:

2000 x 500 = 1,000,000

This gives us an estimation of 2149 x 493 as around 1,000,000. This method is more accurate than rounding, but it requires some familiarity with numbers and their properties.

Conclusion

Estimating multiplication is a useful skill that helps us to quickly solve problems and check our answers. We can use rounding, compatible numbers, or other strategies depending on the context and our level of comfort with numbers. However, we should always keep in mind that estimation is not exact and that we may need to find the actual result by using other methods.