Algebra Help

Question

The amount of resistance, y, in a circuit varies inversely to the current, x, in the circuit. When 10 ohms of resistance are used in the circuit, 12 amperes of current are present. When 5 ohms of resistance are used in the same circuit, 24 amperes of current are present.

How many ohms of resistance are used in the circuit when 15 amperes of current are present? Round your answer to the nearest hundredth, if necessary.

Answer 1

X and Y are inversely proportional if X = K/Y other ways of saying the same thing Y = K/X or X*Y = K where K is a constant. 

 

Based on the first two results given note that 10*12 = 120, also 5*24 = 120

 

Therefore 15*X = 120 or dividing by 15 on both sides you get X = 120/15 = 8 (answer)