At the start of 2017, a car was worth £12000

value of car decreased by 30% every year for 3 years

what's the value of the car at the start of 2017

Im goin to assume there was a typo and believe you meant 2020 because the price of the car at the start of 2017 is 12000.

Step-by-step explanation:

The answer is 1764

30% of 12000 is 3600 so 12000-3600=8400

30% of 8400 is 5880 so 8400-5880=2520

30% of 2520 is 756 so 2520-756=1764