## Thursday, February 24, 2011

### Chapter 3: Approximation and Estimation - An Introduction (Preparation)

What's the difference between these 2 words - Approximation & Estimation?

On your own, go through the learning activity in the following website
http://www.s-cool.co.uk/gcse/maths/approximations

At the end of the 'visit', you should be able to tell the difference between approximation and estimation, and when each is used in real world...

Write a summary to illustrate the KEY DIFFERENCES between Estimation and Approximation. Submit your write-up as a Comment under this posting.

1. Estimation is a process where you round off the digits in the question to more manageable numbers to operate on, such as 98 to 100 or 2.34 to 2. While Approximation is the group in which Estimation and Rounding are in.

2. In estimation, you round up or down the number to the easiest number to divide with. eg. 289 to 300 or 3.7867 to 4. While approximation is when you round off the answer to a certain number of figures or to the nearest tens , hundreds etc.

3. Approximation is the category where estimation and rounding are in. Estimation helps when you have a difficult problem, and you cannot use the calculator e.g. 796 x 23 when rounded to one significant figure it becomes 800 x 20.

4. Estimation is rounding up the numbers for easier calculation and the answer would still be around the same.
eg. 10.7x13.2≈11x13
=143 (141.24 is the correct answer)
Approximation is rounding up the answer to be able to read it more easily without any decimals etc.
eg. 10.7x13.2=141.24
≈141

5. Estimation is used for rounding up numbers to do easier calculation such as 532x34 can be done like this 500x30 You can get an estimate

Approximation is used for simplification of decimals like 1.1459 can be simplified to 1

6. approximation is simply the rounding of numbers, however estimation is the approximation of a number statement.

7. estimation is rounding up or down the numbers to make sure that they are more whole.whereas approximation is rounding up or down the NUMBERS THAT MULTIPLY OR ADD OR DIVIDE OR MINUS TO MAKE your number.

8. Estimation- Is rounding the number to the nearest something or x significant figures.
e.g: 10.2x21.2 ≈ 10x21
= 210 =)
Approximation is rounding up the number to a whole number
e.g: 10.6x72.2 = 765.32
≈ 765....

9. Estimation is when we round off a complicated number into something simpler to add, subtract, m
ultiply or divide it. (e.g 10.7x2.3=11x2=20) After we estimate the complicated numbers, we will get an 'estimated answer' this whole process is called Approximation.

10. Estimation is used to simplify equations by rounding the numbers in it either up or down.

Approximation is rounding the answer to the either the nearest whole number, tens, hundreds etc so that the answer of the question would be understood more easily.

11. Approximation is rounding of a number or decimal to its nearest in tens or hundreds etc, while estimation is rounding up or down a number to make it easier to calculate.

12. I like Princeton's comment about Approximation involving a process.

13. Estimaion is simply simplifying a number such that they are easier to calculate. While approximation would be rounding a number up or down e.g. 6.9 x 7.3 ≈ 7 x 7 = 49

14. Approximation i rounding off a number or decimal to the nearest number or decimal while estimation is rounding a number to the nearest 10s or 100s.

15. Approximation is rounding of complicated numbers in to simple whole numbers so that they would it would be easier to times,divide,subtract,add any whole numbers while estimation is the rounding of numbers to the nearest tens, hundreds or even thousands

16. Approximation is rounding off a number to a simple number so its less complicated to plus, minus, times, divide or other things. Estimation is rounding off a number to a wider range of numbers. Approximation is more precise than Estimation.

17. Approximation: Will happen when a numerical number is either unknown or hard to obtain. It will also happen to irrational numbers, like Pi.
Estimation: Rounding off any number to the nearest whole number.

18. Approximation consists of estimation and rounding.
Estimation is to simplify equations so that they can be done easily.
Rounding is to focus on one digit of a number instead of focusing on all numbers.