Write an equation system based on the problem We can write the equation for "Twice the price in Japan minus five times the price in India is $20.60" as ∴ 2j - 5i = 20.6 <em>(first equation)</em> We can write the equation for "Thirty cents less than three times the lowest price is thirty cents" as ∴ 3i - 0.30 = 0.30 <em>(second equation)</em>
Solve the equations First, solve the second equation to find the price in India 3i - 0.3 = 0.3 3i = 0.3 + 0.3 3i = 0.6 i = 0.6/3 i = 0.2
Second, solve the first equation by subtitution of the value of i to the equation 2j - 5i = 20.6 2j - 5(0.2) = 20.6 2j - 1 = 20.6 2j = 20.6 + 1 2j = 21.6 j = 21.6/2 j = 10.8
The price in India is $0.20 and the price in Japan is $10.80
