**View Tube Triangulation**

Pete Insley Jones Metropolitan H. S.

606 S. State St.

Chicago IL 60605

(312)534-8600

**Objectives**:

Measuring Distance; Estimating; Averaging; Standard deviation

**Materials Needed**:

Meter sticks, rulers, cut down paper towel cardboard tubes

**Strategy**:

First, get the students to estimate the height of the chalkboard or the

doorway. List the estimates and use a calculator to find the average and

standard deviation.

Stand far enough away so that you can see the entire object in the tube.

Use a proportion to find the height of the object.

** Height of object ** _{ = } **Distance of tube**
Distance to object Length of tube
List the calculations and again find the average and the standard
deviation. Take some time to discuss what they mean again.
Now get a couple of students to measure exactly how big the object is.
Have a prize for the best estimate of measurement.
**Performance Assessment**:

Collect paper with original estimate and calculation of height. Have

students write a short paragraph stating how well they think they did on the

exercise.

**Conclusions**:

You can find percentage error in this lab and it has some new meanings to

the students. Have them find their % of error. You can also find the probable

percentage of error from the standard deviation.

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