All of the following are ways to write 25 percent of N except
A. 0.25 N
B. 25N/100
C. 1/4 N
D. 25 N
The answer is D but I want to know why

Question

All of the following are ways to write 25 percent of N except 
A. 0.25 N
B. 25N/100
C. 1/4 N
D. 25 N
The answer is D but I want to know why

anonymous · Answer

In this case, N is just a variable. Let's make N 100.
A. 0.25*100=25                       25 is 25% of 100 so this checks out. 
B. 25(100)/100=25                  25 is 25% of 100 so this checks out too.
C. 1/4= 0.25(100)=25             25 is 25% of 100 so this checks out as well.
D. 25(100)= 2500                    2500 is greater than 100 so it's more than 100% of 100.

As to why that is, it's because you're multiplying the variable by 25, but that won't get you 25% of the variable.