Mr. Dunston and Mr. Dolland spent $45 all
together. Mr. Dunston and Ms. Campbell
spent $65 all together. If Ms. Campbell spent
3 times as much as Mr. Dolland, how much
did Mr. Dunston spend?

The money spent by Mr. Dunston is $ 35.Given that:-Money spent by Mr. Dunston and Mr. Dolland = $ 45Money spent by Mr. Dunston and Ms. Campbell = $ 65Ms. Campbell spent 3 times as much as Mr. Dolland.We have to find the money spent by Mr. Dunston.Let the money spent by Mr. Dunston be $ x,Let the money spent by Mr. Dolland be $ y and,Let the money spent by Ms. Campbell be $ 3yHence, from the data given in the question, we can write,x + y = 45  ...(1)x + 3y = 65 ... (2)By elimination method, we can write,(2) - (1)2y = 20y = 10x + 10 = 45x = 45 - 10 = 35x = 35Hence, the money spent by Mr. Dunston is $ 35.To learn more about elimination method, here:-https://brainly.com/question/12090959#SPJ1