Find an equation of variation if y varies inversely as x and

Find an equation of variation if y varies inversely as x and y = 7.75 when x = 0.16.

Solution

y varies inversely as x. Therefore y = k/x where k is the constant of proprtionality. Since y = 7.75, when x = 0.16, on substituting these values in the equation, we get 7.75 = k/ 0.16 or, k = 7.75 * 0.16 = 1.24 ( on multiplyong both the sides by 0.16). Thus, the equation of variation is y = 1.24/x .