Answer:
42%
Step-by-step explanation:
Let’s say there are 100 people in the city
Today, 20 use public transport and 80 use their own automobiles
6 months from now, 30% of those using their own car will switch to public transport = 30% x 80 = 24
10% of those using public transport will switch to their own car = 10% x 20 = 2
Therefore, in the future, 20 + 24 - 2 people will use public transport = 42
The answer is therefore 42%