In the above question we have a total number of boys 15.

And we have to select one boy from a group of 15 people. Here we have:

Now by putting the value in the formula we can write:

On simplifying it gives us:

Now we can break the factorial values and it gives the value:

Again we have a total number of girls given 10 .

And we have to select one girl from a group of 10 girls. Here we have :

Similarly as above by putting the value in the formula we can write:

On simplifying it gives us:

Now we can break the factorial values and it gives the value:

Now we will multiply both the values to get the required answer:

By putting the values of both the combination, we have: