Quoting for Twelve Oak Café Stools
A workshop has an order for 12 identical oak café stools. Each stool has a seat 350 mm × 350 mm × 25 mm made from two 175 mm strips, four legs 45 mm × 45 mm × 450 mm, and four rails 25 mm × 75 mm × 260 mm. The supplier sells 25 mm × 200 mm × 2400 mm boards at N$320 each and 45 mm × 45 mm × 2400 mm lengths at N$180 each. Labour is estimated at 3.5 hours per stool at N$80 per hour. Finish and fixings cost N$25 per stool. The workshop adds 10% waste to timber and wants 20% profit on total cost. A 25 mm × 150 mm × 2400 mm board is also available at N$240, but the cutting list has not yet been adjusted for it. The customer wants a firm quotation and a delivery date four weeks away; the workshop can assemble two stools per day.
1. Prepare a cutting list and calculate how many boards and leg lengths to order, including the 10% waste allowance.
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Cutting list per stool: 2 seat strips 175 × 350 × 25; 4 legs 45 × 45 × 450; 4 rails 25 × 75 × 260. For 12 stools: 24 seat strips, 48 legs, 48 rails.
25 mm boards: one 25 × 200 × 2400 board yields six 350 mm pieces (2.1 m used). Ripping each to 175 mm gives six seat strips, enough for three seats. 12 seats therefore need 4 boards. For rails, one 200 mm board ripped into two 75 mm strips yields 9 rails per strip, 18 rails per board. 48 rails need 3 boards. Total 7 boards.
Legs: one 2400 mm length yields five 450 mm legs (2.25 m used, 150 mm waste). 48 legs need 9.6 lengths, so order 10.
Order: 7 × 25 × 200 × 2400 boards and 10 × 45 × 45 × 2400 lengths.
2. Calculate the total cost, cost per stool and a selling price that gives 20% profit on total cost.
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Timber: 7 × N$320 = N$2,240; 10 × N$180 = N$1,800; subtotal N$4,040. Add 10% waste = N$404, so timber = N$4,444. Labour: 12 × 3.5 h = 42 h × N$80 = N$3,360. Finish/fixings: 12 × N$25 = N$300. Total cost = 4,444 + 3,360 + 300 = N$8,104. Cost per stool = 8,104 ÷ 12 = N$675.33. Profit at 20% on total cost = 0.20 × 8,104 = N$1,620.80. Selling price total = N$9,724.80; per stool = N$810.40, so quote about N$815 per stool or N$9,780 for 12.
3. The supplier offers 25 × 150 × 2400 boards at N$240. Explain how using them for the rails changes the order and cost, and state one other way to reduce waste.
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Use 25 × 150 × 2400 boards for the rails. A 150 mm board rips into two 75 mm strips with no width waste, and each strip still yields 9 rails, so 3 boards are still needed. Cost falls from 3 × N$320 = N$960 to 3 × N$240 = N$720, a saving of N$240. New timber cost = 4,040 - 960 + 720 = N$3,800; with 10% waste = N$4,180. Total cost = 4,180 + 3,360 + 300 = N$7,840; per stool = N$653.33; 20% profit gives N$7,840 × 1.20 = N$9,408, or N$784 per stool. Another waste reduction is to use the 300 mm offcuts from the seat boards for small parts such as corner blocks, or to order 25 × 175 boards for the seats so the 25 mm rip waste is eliminated.