Answer:
Option D.
Step-by-step explanation:
It is given that a satellite is composed of 30 modular units. Each unit contains the same number of non-upgraded sensors.
Let x be the total number of upgraded sensors on the entire satellite.
The number of non-upgraded sensors on one unit is 1/5 the total number of upgraded sensors on the entire satellite.
Non-upgraded sensors on one unit = [tex]\frac{1}{5}x[/tex]
Non-upgraded sensors on 30 unit = [tex]30\times \frac{1}{5}x=6x[/tex]
Total number of sensors on the entire satellite is the sum of upgraded and non-upgraded sensors
[tex]Total=x + 6x = 7x[/tex]
We need to find the fraction of the sensors on the satellite have been upgraded.
[tex]Fraction=\frac{\text{Upgraded sensors}}{\text{Total sensors}}[/tex]
[tex]Fraction=\frac{x}{7x}[/tex]
[tex]Fraction=\frac{1}{7}[/tex]
Therefore, the correct option is D.
