Pierce works at a tutoring center on the weekends. At the center, they have a large calculator to use for demonstration purposes that is a scale model of calculators available for the students to use.
Each key on the student calculators is 15 millimeters wide, and each key on the demonstration calculator is 3 centimeters wide. If the student calculators are 246 millimeters tall, how tall is the demonstration calculator?
A.
0.03 meter
B.
0.492 meter
C.
49.2 meters
D.
7.38 meters
B. 0.492 meter
To find the height of the demonstration calculator, we can set up a proportion:
3 cm (width of key on demonstration calculator) / 15 mm (width of key on student calculator) = x / 246 mm (height of student calculator)
Cross multiply:
3 * 246 = 15x
738 = 15x
x = 49.2 mm
Converting mm to meters:
49.2 mm = 0.0492 meters
Therefore, the height of the demonstration calculator is 0.492 meters.