Geometry and TrigonometryEasy–MediumAngles of a triangle in a ratio
Geometry and Trigonometry practice question
The measures of the three angles of a triangle are in the ratio 3 : 4 : 5. What is the measure, in degrees, of the smallest angle?
Answer: 45
The ratio has 3 + 4 + 5 = 12 parts, and the angles total 180°, so each part is 15°. The smallest angle is 3 × 15 = 45°.
Common wrong answers
- If you answered 15
- 15 is the size of one part; the smallest angle has 3 parts.
- If you answered 60
- 60 is the middle angle (4 parts).
- If you answered 75
- 75 is the LARGEST angle (5 parts). The question asks for the smallest.
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- Easy–Medium
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A circle has a radius of 5. What is its circumference? (Use C = 2πr.) - Easy–Medium
What is the midpoint of the segment joining the points (2, 3) and (8, 11)? - Easy–Medium
What is the measure, in degrees, of angle B? - Easy–Medium
What is the area, in square centimeters, of the trapezoid?
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