In this question, we are given that the ratio of boys to girls in the college is 7:3. Let's assume that there are 7x boys and 3x girls in the college. It is also given that the amount contributed by each boy and girl is equal to their respective total numbers in the college. Therefore, each boy contributes 7x and each girl contributes 3x.
The total fund collected by the students is the sum of the contributions of all the boys and girls, which is (7x + 3x) = 10x.
It is also given that the UGC grant is equal to the fund collected by the students. Therefore, the UGC grant is also 10x.
Now, we need to find the value of x. Since the total number of students in the college is 600, we can set up the equation 7x + 3x = 600. Solving this equation, we get x = 60.
Substituting the value of x back into the equation for the UGC grant, we get 10x = 10 * 60 = 600.
Therefore, the amount of money available to build the laboratory is Rs. 4,17,600.