If 1mm = 500km then:
7000km/500km will give you your diameter of the drawing.
This means the planet drawing will have a diameter of 14mm
If you see the below statements among the choices, then you can select these as the answers:
a.) 39 + 2k = 69
2k = 69 - 39
2k/2 = 30/2
k = 15
b.) 39 + 2k = 69
39 + 2(15) = 69
39 + 30 = 69
69 = 69
This ones a bit tricky but the answer is A
