MATHEMATICS
JAMB 2010 - Question 17
Mathematics 2010 JAMB Past Questions - Question 17: If y varies directly as the square roots of x and y=3 when x=16.calculate y when x=64.
A:
B:
C:
D:
Correct Answer
C
Explanation
Y ∞ √x , i.e y = √x3 = k √16 = 4k ¾ =k , y = ¾ √64 = ¾ X 8/1 y =6If y varies directly as the square root of x, we can write the equation as y = k√x, where k is the constant of variation.To find the value of k, we can substitute the given values of x and y into the equation and solve for k.When x = 16 and y = 3:3 = k√163 = 4kDivide both sides by 4:k = 3/4Now that we have the value of k, we can use it to find y when x = 64.y = (3/4)√64y = (3/4) * 8y = 6Therefore, when x = 64, y = 6.

