Your question is not clearly stated. Do you mean the difference between 10 * 10 * x, and 7 * 7 * 7 *x ? Then the number is x = 119/243. That's about 0.48971... in decimal form.
It's confusing when you say the "difference of a number". Differences are BETWEEN two numbers. See what I mean?
The transaction of this is
Cash. Increase by 750
12.T
13.F
14.F
15.F.
16.???(where is 16?:O)
17.T
18.T
19.T
20.???(where is 20?)
21.5
22.5
The answer to this question would be x=a2y2
Okay so instead of dividing you will cross multiply.
4n(15)=84(5)
60n=420
420/60=7
Answer: n=7