Mathematics 2003 JAMB Past Questions - Question 12: x varies directly as the product of u and v and inversely as their sum.if x=3 when u=3 and v=1,what is the value of x if u=3 and v=3?

Correct Answer

C

Explanation

To solve this problem, we can use the direct and inverse variation formulas.Let's denote x as the variable that varies directly with the product of u and v, and inversely with their sum. We can write the equation as:x = k(uv)/(u+v)where k is the constant of variation.Given that x = 3 when u = 3 and v = 1, we can substitute these values into the equation to find the value of k:3 = k(3*1)/(3+1)3 = 3k/4To solve for k, we can multiply both sides of the equation by 4/3:4/3 * 3 = kk = 4Now that we have the value of k, we can find the value of x when u = 3 and v = 3:x = 4(3*3)/(3+3)x = 36/6x = 6Therefore, when u = 3 and v = 3, the value of x is 6.