please help
What distance is traveled by a satellite 1200 km from the center of the Earth in 40pi rotations?

Question

please help 
What distance is traveled by a satellite 1200 km from the center of the Earth in 40pi  rotations?

anonymous · Answer

these are the choices 
A) 48,000
 B) 150,796
 C) 225,000
 D) 250,435

anonymous · Answer

@hartnn   turns out that the " l " symbol is  actually  Pi  (3.1415)

hartnn · Answer

in one rotation, satellite will cover one circumference distance. 
right ?

anonymous · Answer

so 1200 is the radius  r

anonymous · Answer

circum. =2 Pi r   so  2 x 3.1415 x 1200

hartnn · Answer

in 40pi rotations, distance covered = 40pi times circumference

$D =40\pi (2\pi r) $

hartnn · Answer

none of the option match...

anonymous · Answer

yes that is the problem :(

hartnn · Answer

you sure about being "pi" ?

anonymous · Answer

yes the teacher replied back and said it is pi

anonymous · Answer

is there any other way to solve this ?

hartnn · Answer

$40\pi r = 40 \pi (1200) = 150796$

anonymous · Answer

thats B , in the choices

anonymous · Answer

i think this is the answer , right ?

hartnn · Answer

its like saying, that in 2pi rotations, distance covered is 'r' 
so in 40pi rotations, distance covered will be 40pi r 
does not seem quite correct...logically.

hartnn · Answer

Logic says, distance covered in one rotation = 2pir

anonymous · Answer

i see but it is the closest in the choices

anonymous · Answer

yes in one rotation so its covering the circum. of the circle

hartnn · Answer

given those choices, preferable to probably pick up B) only .
if and when you get an explanation for this, share with us. 
@ganeshie8 might get some sense out of it...

hartnn · Answer

probably $\Large 2\pi$ rotations would mean $\Large 1 $ round around the earth. 

so , 40pi rotations would mean only 40pi/2pi = $\Large 20$ rounds of earth 
giving 20* (2pi r) = 150796 km distance

anonymous · Answer

yes I wanted to post in the yesterday's post but unfortunately its closed.
so as soon as I'll get the explanation . I will post a new post and share it with both of you.

anonymous · Answer

probably , thats the best and closest explanation so far ,
thank you so much  for your effort @hartnn

anonymous · Answer

I'll share the explanation as soon as I'll get it

hartnn · Answer

thanks :)
and welcome ^_^