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 (first equation)
We can write the equation for "Thirty cents less than three times the lowest price is thirty cents" as
∴ 3i - 0.30 = 0.30 (second equation)
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