precentage?

I'm not sure what you mean, but if you mean something like:

What is 5% of 25?

25/100 = X/5

Solve for X:

(25 * 5) = 100 * X

125 = 100 * X

125/100 = X

X = 1.25

Ideally the formula is straightforward,

(Number / Total Number) * 100

But questions in papers always complicated Eg.

1. What is the percentage of A in the total of B?

Ans : (A / B) * 100

2. What is the percentage of A species in the container that having B, C and D species

Ans : A / (A+B+C+D) x 100

3. What is the total of the species if given A is only 40% which is also equivalent to x?

Ans : ......

165/733=x/100 put these over each other, then cross multiply and solve for x. I'm not giving you the answer ,sorry, but I'll help you get it.

I'm not sure what you mean, but you can use porportions to solve this problem. ( 165/733 =variable/100 ). then just cross multiply(16500=733*variable)and solve for the variable.

Percentage of two numbers

find what percentage 10 is of 100

10 ÷ 100 = 0.1 decimal approximation

0.1 x 100 = 10 %

Multiplying decimal approximation 0.1 by 100 equals 10%

Do you mean a question such as; what percentage of a2 is a1?

If so;

Take the number number a1 and divide it by the number represented as "100%" (a2)

add both of the numbers together and then divide by 2