Describe three strategies for estimation.
Estimation involves approximating or making an educated guess about a value or quantity. There are several strategies for estimation, and here are three commonly used ones:
1. Rounding: This strategy involves rounding numbers to make calculations easier and quicker. For example, if you need to estimate the sum of 47 and 82, you can round them to 50 and 80, respectively. Now, adding 50 and 80 gives you an estimated sum of 130. Rounding can be used in various ways depending on the specific estimation task.
2. Front-end estimation: In this strategy, you focus on the digits at the front or leftmost side of the numbers involved. It involves disregarding the rest of the digits. For example, if you want to estimate the product of 25 and 43, you would multiply only the front digits, which are 20 and 40, giving an estimated product of 800. Front-end estimation provides a quick and rough approximation.
3. Compatible numbers: This strategy involves selecting numbers that are compatible or easy to work with for estimation purposes. For instance, if you need to find an estimate for the quotient of 382 divided by 12, you could round both numbers to more compatible values, such as 380 and 10. Dividing 380 by 10 gives an estimated quotient of 38. Compatible numbers simplify calculations and provide convenient estimates.
To utilize these strategies effectively, it is important to consider the context of the problem and the level of accuracy required for the estimation.