Explanation:
Well since it cost 6$ and the price was 0.36 you can calculate how many gallons you needed to fill up your tank which is calculated by dividing the price to fill the gas tank by the price per gallon
6/0.36 = 16.667 gallons
Now multiply the amount of gallons you need to fill your gas tank by the price in 2010
16.667 * 2.84 = 47.36
You could also just look at the price as a percentage relative to 1970 prices and see that the price increased by 788.9% and the find what 788.9% is of 6$. Which can be done by dividing 788.9 by 100 to convert it into decimal form which gives you 7.889 and then multiply that by the original price of 6$ to fill your gallon to get 47.33 which is slightly different although this is likely due to rounding.