Answer: 100.8 centimeters
Step-by-step explanation:
Given: At the center, there is a large calculator to use for demonstration purposes that is a scale model of calculators available for the students to use.
Let x be the length of the demonstration calculator.
Since both are similar, by direct proportion we have,
[tex]\\\Rightarrow\ \frac{\text{length of key on demonstration calculator}}{\text{length of key on student calculator}}=\frac{\text{Height of demonstration calculator}}{\text{Height of student calculator}}\\\\\Rightarrow\ \frac{6.8}{17}=\frac{x}{252}\\\\\Rightarrow\ x=\frac{6.8\times252}{17}\\\\\Rightarrow x=100.8[/tex]
Therefore, the demonstration  calculators are 100.8 centimeters tall.
