In the following pie-chart, the distribution of the number of cars in four major cities is given. In…

The number of petrol cars in City B is $\frac{7}{13} \times 26\%$ $= 14\%$ of the total cars (or $20,580$), so 20% of them equals $0.20 \times 14\% = 2.8\%$ of total cars (or $4,116$ cars). The number of petrol cars in City C is $\frac{3}{8} \times 32\%$ $= 12\%$ of the total cars (or $17,640$), so 25% of them equals $0.25 \times 12\% = 3.0\%$ of total cars (or $4,410$ cars). Their ratio is $2.8 : 3.0$ $= 28 : 30$ $= 14 : 15$.