Prius = 58 city / 53 highway
Corolla = 30 city / 42 highway
Say even balance of both, 50.5 mpg Prius, 36 mpg Corolla.
Gasoline consumption per 150,000 miles (ten year life) is 2970 gallons for the Prius, 4267 for the Corolla, a difference of 1196 (say 1200 gallons). If the price of the Prius is 7000 more, gas would have to be 7000/1200 = $5.83 dollar per gallon to break even. This ignores the price of money, which favors the Corolla, because Prius is upfront money.
If I assign a cost of money to the $7000 up front cost at 6% per year, the price of gas would have $7.92 per gallon to break even. YMMV.
Some people prefer the Prius. Good for them.
I used 27mpg for the Corolla. If it is well over 30mpg then it has a 100,000 mile advantage over the Pious.
The wife had a Corolla for a work provided car. It wasn’t bad. It isn’t a BMW, but it did well overall. For comfort and ride, not to mention safety, I’d take a Corolla over a Pious any day. I’d say the Corolla is one of the best small cars on the road, especially at $22,000.