Automobiles are the most preferred mode of transport because they allow us to cover large distance quickly. Resultantly, vehicles have been developed that run on diesel, petrol and even on electricity, which is a remarkable innovative development. During a survey about the percentage wise distribution of cars in four different states, the information regarding ratio between the diesel engine cars, petrol engine cars and electric cars was collected. Total number of cars for which data was collected was 8000. Of these, State 1 had 15% of the total cars in the ratio of 3:4:1 (diesel, petrol and electric); State 2 had 20% of the total cars in the ratio of 5:3:2 (diesel, petrol and electric); State 3 had 30% of the total cars in the ratio of 4:5:3 (diesel, petrol and electric), and; State 4 had 35% of the total cars in the ratio of 7:5:2 (diesel, petrol and electric).

Compute the percentage of total electric cars to total cars in all the States.

The correct option is 18.37%.

To find the percentage of total electric cars to total cars across all four states, we first calculate the number of electric cars in each state and then determine their total count.

Step 1: Understand the given data

The total number of cars across all four states is 8000.

The ratio of cars in each state is given as Diesel : Petrol : Electric.

Step 2: Calculate the number of electric cars in each State

State 1:

Total cars in State 1 = 15% of 8000

$\text{State 1 total cars}=\frac{15}{100}\times 8000=1200$

The ratio for State 1 is 3 : 4 : 1. The total parts in the ratio = 3 + 4 + 1 = 8.

Electric cars share = 1 part out of 8 parts.

$\text{Electric cars in State 1}=\frac{1}{8}\times 1200=150$

State 2:

Total cars in State 2 = 20% of 8000

$\text{State 2 total cars}=\frac{20}{100}\times 8000=1600$

The ratio for State 2 is 5 : 3 : 2. The total parts in the ratio = 5 + 3 + 2 = 10.

Electric cars share = 2 parts out of 10 parts.

$\text{Electric cars in State 2}=\frac{2}{10}\times 1600=320$

State 3:

Total cars in State 3 = 30% of 8000

$\text{State 3 total cars}=\frac{30}{100}\times 8000=2400$

The ratio for State 3 is 4 : 5 : 3. The total parts in the ratio = 4 + 5 + 3 = 12.

Electric cars share = 3 parts out of 12 parts.

$\text{Electric cars in State 3}=\frac{3}{12}\times 2400=600$

State 4:

Total cars in State 4 = 35% of 8000

$\text{State 4 total cars}=\frac{35}{100}\times 8000=2800$

The ratio for State 4 is 7 : 5 : 2. The total parts in the ratio = 7 + 5 + 2 = 14.

Electric cars share = 2 parts out of 14 parts.

$\text{Electric cars in State 4}=\frac{2}{14}\times 2800=400$

Step 3: Calculate the total number of electric cars

$\text{Total Electric Cars}=150+320+600+400=1470$

Step 4: Compute the percentage of total electric cars to total cars

$\text{Percentage}=\left(\frac{1470}{8000}\right)\times 100\%$

$\text{Percentage}=\frac{147}{8}\%=18.375\%\approx 18.37\%$

Thus, the percentage of total electric cars to total cars in all the States is 18.37%.