I think the answer to this is a rate
Answer:
-3
Step-by-step explanation:

First, you can factor out a 6:

Next, you can factor the quadratic:

Since the only value of x that could set this equation equal to 0 is -3, that is the answer. Hope this helps!
0.4x 0.4x 0.4 = (0.4)^3
Exponential form = (0.4)^3
The Answer is C 5/6
250/300 reduced and simplified is 5/6
Multiply 140 on both sides to get "x" by itself


8 = x