How do you find #f(20)#, if #f(x)# varies inversely with #x# and #f(12)=5#? Algebra Rational Equations and Functions Inverse Variation Models 1 Answer Shwetank Mauria May 10, 2018 #f(20)=3# Explanation: As #f(x)# varies inversely as #x#, we have #f(x)=k*1/x# and as #f(12)=5#, we have #k*1/12=5# i.e. #k=12xx5=60# Hence #f(x)=60*1/x=60/x# and #f(20)=60/20=3# Answer link Related questions What are Inverse Variation Models? How do direct and inverse variation differ? How do you solve inverse variation problems? How is inverse variation used in everyday life? How do you find "k" if y varies inversely as x and if #y=24# when #x=3#? How do you find y when #x=12# if y is inversely proportional to x and #y=2# when #x=8#? If y varies inversely as x, how do you find the constant of variation if #y=36# when #x=9#? If y varies directly as x and inversely as the square of z and if #y=20# when #x=50# and #z=5#... If y varies indirectly as the cube of x, and k is the constant variation, how do you find the... If y varies inversely as x and y = 40 when x = 16, how do you find y when x = 10? See all questions in Inverse Variation Models Impact of this question 7040 views around the world You can reuse this answer Creative Commons License