-189/ 64, 63/ 16, -21/4, 7 . . . I know it's a geometric sequence and I know the top is multiplied by a negative number. Help?

Question

I really need help with this problem. I know for sure the top is multiplied by a negative, this would explain the jumping back and forth between positives, but that's it. Help?

Answer 1

In this sequence, the numerators are divided by -3,

-189 ÷ -3 = 63; 63 ÷ -3 = -21; -21 ÷ -3 = 7

 

and the denominators are divided by 4

64 ÷ 4 = 16; 16 ÷ 4 = 4; 4 ÷ 4 = 1

 

So, the last value is 7/1 = 7