The 2nd term in a geometric sequence is 20 the 4th term in the same sequence is 45/4 or 11.25 what is the common ratio?

Let x be the common ratio and y be the 3rd term

11.25/x=y This means the fourth term divided by the common ratio will get the third term

20x=y This means the second term multiplied by the common ratio will get the third term

11.25/x=20x Set the two y's equal to each other, and solve for x!

20x^2=11.25

x^2=.5625

x=+-√.5625

x=.75 or -.75