Answer:
Howard's order will contain 15 boxes of hammers and 39 boxes of wrenches.
Explanation:
1. Let's review the data given to us for solving the question:
Price of box of wrenches = US$ 100
Price of box of hammers = US$ 300
Cost of the order = US$ 8,400
2. Let's find the exact amount of boxes of wrenches and hammers
Cost of the order = Price of box of wrenches * Number of boxes of wrenches + Price of box of hammers * Number of boxes of hammers
Replacing with the real values:
8,400 = 100 * 40 + 300 * Number of boxes of hammers
8,400 = 4,000 + 300 * Number of boxes of hammers
- 300 * Number of boxes of hammers = 4,000 - 8,400
- 300 * Number of boxes of hammers = -4,400
Number of boxes of hammers = -4,400/300 = 14.67 ≈ 15
For making a order without fractions or decimals of a box, it will contain just whole numbers, this way:
15 boxes of hammers + 39 boxes of wrenches
Cost of Howard's order = 15 * 300 + 39 * 100 = 4,500 + 3,900 = 8,400