Develop Program in asp.net need logic

i want to develop this type of Program.

Credit card verification for user by adding 2 different amount in ration of 10$

like 5$ + 5$ or 6$ + 4$

you can see the perfect example on ODESK site.

i want to develop that type of functionality for verify for real user.

also what is the logic behind 2 different amount?

i am very confused about this.

 

there is already an API code for the same ... you need not to start from scratch ..... just do googling

 

can you give me this type of API code?

also can anyone tell me what is the logic behind 2 amount why they not cut 1 singal amount.

 

So you want to randomly generate a number between 1 and 9 and then deduct this from 10 to calculate the other number?

Why are you doing this? Sounds like your using it to check its a real person answering the question but it doesnt work as such if the answer is always 10

 

i want to develop odesk type credit card verification functionality.

 

Don't have an awareness of odesk but to answer the question of logic - generate 2 whole numbers that equal a total of 10, generate 1 number between 1-9 and deduct it from 10 to generate the second.

 

yes but why they cut 2 number?

why they cannot cut 3 number?