Answer:
is the common ratio
Step-by-step explanation:
Common ratio(r) states that the ratio of each term of a geometric sequence to the term preceding it.

Given the sequence:
225, 45, 9, .........
Here,


and so on...
Using definition to find r.

After solving we get;

Therefore, the common ratio is, 
C. because the decimal is never ending, so it is irrational.
Answer:
<em>29 minutes more</em>
Step-by-step explanation:
Let m represent minutes
changing the statement to algebra, since the second company charges a different rate at night and weekend we have the equation below;
$19.99 + $0.35m > $29.99
Subtract 19.99 from both sides to isolate m and we have;
$19.99 -$19.99 + $0.35 > $29.99 - $19.99
= $0,35m > $10.00
Divide both side by 0.35 to obtain the value of m;
> 
= m > 28.57
<em>m ⩾ 29 minutes</em>
<em>The second company's will be twenty nine minutes or more costlier than the first company</em>
Answer:
Step-by-step explanation:
1) Eliminate parentheses:
0.1x +18.8 = -4 +2x
22.8 = 1.9x . . . . . . . . . add 4 - 0.1x
12 = x . . . . . . . . . . . . . divide by 1.9
__
2) Eliminate parentheses:
-16 +4x = 0.8x +12.8
3.2x = 28.8 . . . . . . . . add 16 - 0.8x
x = 9 . . . . . . . . . . . . . .divide by 3.2
_____
<em>Comments on the solutions</em>
The expression we add in each case eliminates the constant on one side of the equation and the variable term on the other side. That leaves an equation of the form ...
variable term = constant
We choose to eliminate the smaller variable term (the one with the coefficient farthest to the left on the number line). Then the constant we eliminate is the on on the other side of the equation. This choice ensures that the remaining variable term has a positive coefficient, tending to reduce errors.
__
You can work these problems by methods that eliminate fractions. Here, the fractions are decimal values, so are not that difficult to deal with. In any event, it is good to be able to work with numbers in any form: fractions, decimals, integers. It can save some steps.