Subject: estimates

I am looking for examples of estimates for underestimating and overestimating. When would you do each one. For my child age 11 6th grade.
Sue Jordan

Hi Sue,

Suppose that your daughter went to a free concert in the local concert hall and she wanted to estimate the number of people who where there. She lookad around and saw that everyone was seated and there were still some empty seats. So the number of seats in the hall is an overestimate on the number of people at the concert. She also noticed that all the seats on the main floor were filled and the vacant seats were in the balcony. In this case the number of seats on the main floor is an underestimate of the number of people at the concert.

For an example where you might want to overestimate suppose you go shopping with $55.00. The items that you want to buy cost $49.76 and there is a sales tax of 7%. Do you have enough money? An overestime of the price is $50.00 so an overestimate of the tax is 7% of $50.00 which is $3.50. Thus an overestimate of the cost is $53.50 and you have enough money.

On the other hand suppose that you are on a trip, you are approaching a gas station and there is a sign that says "Last service station for 50 miles". You look at your gas gauge and estimate how many miles you can go without purchasing more gas. Here you want an underestimate because if you overestimate and think you have enough gas for 50 miles but you don't, you may have to walk.

Go to Math Central