Assume, Planet I is x million miles from Sun,

Planet II is y million miles from Sun and

Planet III is z million miles from Sun

Accordingly x-y = 33.2, (1)

z-x = 26.6 (2)

and x+y+z =195 (3)

Subtract eq (2) from (1), 2x-y-z=6.6, or y+z= 2x-6.6

Substitute for y+z in eq (3) 3x- 6.6= 195 or 3x= 201.6 or x= 67.2

Substitute for x in eq (1) , y= 6 million miles from the Sun… Answer

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