For anyone wondering, a 172 can hold 3 adults including the pilot, cruises at 115mph, and burns about 9 gallons of fuel per hour so it gets 12.8 miles per gallon. A Learjet 45 can hold 11 people, cruises at 510mph, and burns about 200 gallons per hour so it gets 2.2 mpg. A Boeing 787-9 can hold 290 people, cruises at 560mph, burns 2000 gph, and gets 0.28mpg.
The 172 uses 2.63 gallons per person to go 100mi, the Learjet uses 4.06 gallons, and the 787 uses 1.23.
A 2022 Toyota Corolla gets around 40mpg highway and squeezes 5 people inside so it uses 0.5 gallons per person per 100mi.