Geometry

Question Analysis

This question involves using a protractor to measure an angle. The main focus is on correctly identifying the scale and calculating the angle measurement without a clear 0 - degree start.

 

Key Concept Explanation

A protractor has two scales (inner and outer). When one side of the angle doesn't start at 0°, we find the difference between the scale values where the two sides of the angle intersect the same scale.

 

Step - by - Step Solution

1. Determine the scale

Observe that the initial side of the angle is closer to the left - hand side  of the protractor, so we use the outer - ring scale.

 

The outer - ring scale reading of the initial side is .

The outer - ring scale reading of the terminal side is .

 

2. Calculate the angle:

Since the outer - ring scale increases counter - clockwise, the angle measurement is

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