Question

Each key on the student calculators is 15 millimeters wide, and each key on the demonstration calculator is 4.5 centimeters wide. If the student calculators are 250 millimeters tall, how tall is the demonstration calculator?

Answer 1

The answer to your question is 75 cm

Explanation:

Data

Student calculator Demonstration calculator

width = 15 mm width = 4.5 cm

height = 250 mm height = ?

Process

1.- Convert the width of the demonstration calculator to mm

10 mm ---------------- 1 cm

x ---------------- 4.5 cm

x = (4.5 x 10) / 1

x = 45 mm

2.- Use proportions to find the height of the demonstration calculator

250 / 15 = x / 45

- Solve for x

x = (250 x 45) / 15

-Simplification

x = 11250 / 15

-Result

x = 750 mm

3.- Conclusion

The height of the demonstration calculator is 750 mm or 75 cm