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.

Question

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

Answer 1

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.