Answer:
(Choice B) B It decreases.
Step-by-step explanation:
According to the situation, the solution of the value of the expression is as follows
Let us assume
r 80 -2r
5 80 - 10 = 70
4 80 - 8 = 72
3 80 - 6 = 74
2 80 - 4 = 76
1 80 - 2 = 78
As we can from the above calculation that expression value risen if r value decreased
Therefore the correct option is B.
Answer:
75% bigger
Step-by-step explanation:
Let the first number be x and the second be y.
So:

And:
-----30% less than x
Substitute
in 




Cross multiply


Collect like terms


Make x the subject


So, the average is:




Rewrite as:

Express as percentage

This means that the average is 75% bigger than the second number
Answer:
C or D as they are Identical
Step-by-step explanation:
Answer:
B.2r+6=30
Explanation:
It costs $6 dollars just to get in. Subtract 6 from 30. 30-6=24
Divide 24 by 2. 24 divided by 2 equals 12.