Deck BuildingMath brain teasers require computations to solve.
Ralph wanted to buy all the lumber for his deck in one trip, and not have to go back to the lumberyard 45 miles away. He didn't want to buy more than he needed because wood is expensive and he had nowhere to store it.
Ralph's plans for his deck called for standard 2x4 - 8 foot long pine boards with 3/8" spacing between each board for drainage. His deck was to be 8 feet deep by 30 feet long. The last board farthest from the doorwall could be cut lengthwise to fit if necessary, thus giving him a smaller width board at the end where no one is likely to see it.
How many 2x4's did he buy?
HintThe boards are to be laid flat, not on end. No tricks in the deck layout, the board placement, or the 3/8" drainage spacing.
AnswerHe purchased (93) 2x4's with no cutting required (not 83 boards). Standard 2x4 lumber is actually 1.5" x 3.5" in size.
30 foot = 360 inches = x (3.5") + (x-1) (0.375")
where x is the number of boards
Lumber is referred to by its nominal size, in this instance, 2x4. It starts out as 2" x 4" when it is first rough sawn from the log. It is then dried and planed to its finished size of 1.5" x 3.5".
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