PLEASE EXPLAIN HOW TO FIND THE COMMON RATIO FOR THE GEOMETRIC SEQUENCE

Question

16, 40. 100,____, ____

AND

81,54, ______,______,______

Answer 1

40/16=2.5

100/4=2.5

2.5*100=250

250*2.5=625

16,40,100,250,625

81/54=1.5

81*1.5=121.5

121.5*1.5=182.25

182.25*1.5=273.375

81,54,121.5,182.25,273.375