Respuesta :

Answer:

30 is the geometric mean between 9 and 51.

Step-by-step explanation:

i multiplied 30 by 2 because there are two numbers in the set of numbers that have a mean of 30.

30*2=60

i then subtracted 9, working back from finding the mean,

60-9=51.

check your work!

51+9=60/2=30

your answer is 51