Posted by **B.B.** on Wednesday, June 10, 2009 at 12:11pm.

Here is the original question: Give an estimate for the following expression: 978*66. Is the exact answer going to be greater than or less than the estimate? Here is what I have: I rounded 978 to 1000 and 66 to 70. 1000*70=70,000 the actual answer was 978*66=64,448 so the estimation was greater than the actual answer. Did I do this problem right? I used the rounding technique. Thanks.

- Math -
**MathMate**, Wednesday, June 10, 2009 at 12:22pm
The answer is correct.

However, you may want to review your reasoning.

What you said

*I rounded 978 to 1000 and 66 to 70. 1000*70=70,000 the actual answer was 978*66=64,448 so the estimation was greater than the actual answer.*

seems to tell me that you conclude that you were over-estimating **after** calculating the exact answer, which is not what is intended.

You are expected to determine if you answer is over- or under-estimating **without** calculating the exact answer.

Your teacher may prefer to see a reasoning as follows:

"I rounded 978 to 1000 and 66 to 70. 1000*70=70,000. Since I rounded **up** both multiplicands, the estimation was greater than the actual answer.

Check: 70000>978*66=64,448"

## Answer This Question

## Related Questions

- Math - Here is the question: Give an estimate for the following expression. Then...
- Math - I need some help. Here is the problem: Give an estimate for the following...
- Math - I cannot figure this problem out. I have did it several ways and get ...
- statistics - Give an estimate for each expression in Exercises, Then state ...
- calculus - consider the initial value problem dy/dx=y^2+1, y(0)=0. estimate y(2...
- 3rd grade math - i need help!! if the estimate is greater than or equal or 1,500...
- Math - Here is the question: Find the exact value of the following expression: 6...
- Math...Applying the Order of Operations - Can you please show me where i'm going...
- Math - if you use $63.00 divided by 9 to estimate $62.59 divided by 9 $7.00 ...
- math - magnitude estimate for 9.3*2.8=_ The exact answer for 9.3*2.8 is 26.04, ...

More Related Questions