Mr.Indigo purchased some trees to plant in his backyard.He bought three oak trees for 23 dollars each and an elm tree for 42 dollars.What was the total cost of the trees?
It's division or Multiplication.[just to let you know]

oak tree = $23
oak tree = $23
oak tree = $23
elm tree = $42

Mr.Indigo purchased some trees to plant in his backyard.He bought three oak trees for 23 dollars each and an elm tree for 42 dollars.What was the total cost of the trees?

three oak trees plus one elm tree equals total cost.
3 oak +1 elm = total cost.
substitute the variables with numbers.
3(23) + 1(42) = ?
69 + 42 = ?
111