So, since she weights 6 times more on earth, say for every lb on the moon is 6lbs on earth then.
now, if 1lb on the moon is 6lbs on earth, how much is 90 earth lbs on the moon?
The function modelled by the height (x) of the tree is as follows:
y - 180 = (368 - 180)/(7 - 3) (x - 3)
y - 180 = 47(x - 3) = 47x - 141
y = 47x - 141 + 180 = 47x + 39
Therefore, after 10 years, the tree will be 47(10) + 39 = 470 + 39 = 509 cm tall