Question 4.2.9: The Eastside Nursery ordered 27 tree seedlings. Some of the ......

Let x represent the number of elm seedlings in the shipment. Since the shipment contained 27 seedlings, the number of maples is found by subtracting the number of elms from 27.

27 – x = number of maples

If each elm seedling costs $17, then x elm seedlings will cost 17x dollars. Also, the cost of (27 – x) maple seedlings at $11 each is 11(27 – x). The total cost of the shipment was $375. A table can be very helpful in identifying the knowns and unknowns.

The information in the table is used to develop the following equation.

Cost of elms + Cost of maples = Total cost

17x        +     11(27 – x)          =    375

Now solve this equation.

17x + 297 – 11x = 375    Use distributive property.

                 6x + 297 = 375    Combine terms.

                            6x = 78      Subtract 297 from each side.

                             x = 13       Divide each side by 6.

There were x = 13 elm seedlings and (27 – 13) = 14 maple seedlings.