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Problem of the Week
Problem B and Solution
Jafar’s New Floor


Jafar is laying new hardwood flooring in his rectangular living room, which has an area of \(66~\text{m}^2\). Each box of flooring has \(8\) identical wooden planks, and each plank has an area of \(0.2~\text{m}^2\).

  1. Assuming that there is no waste, how many planks will he need to cover the floor of his living room?

  2. If Jafar wants to buy an extra \(10\%\) for waste, how many boxes of flooring does he need to buy?

  3. If each box costs \(\$74.50\) and sales tax is \(15\%\), what will be the total cost of the flooring in part (b)?


  1. The area of the living room floor is \(66~\text{m}^2\) and each plank has an area of \(0.2~\text{m}^2\). So the total number of planks needed is \(66 \div 0.2 = 330\).

  2. The extra amount is \(10\%\) of \(330\), which is \(0.10 \times 330=33\) planks.

    So in total Jafar wants to buy \(330+33 = 363\) planks. Since there are \(8\) planks in each box, the number of boxes required is \(363 \div 8 = 45.375\). Therefore, he should buy \(46\) boxes.

  3. Jafar wants to buy \(46\) boxes, and each box costs \(\$74.50\). The total cost before tax is \(46 \times \$74.50 = \$3427\).

    The amount of tax is \(15\%\) of \(\$3427\), which is \(0.15 \times \$3427 = \$514.05\).

    Therefore, the total cost of the flooring is \(\$3427 + \$514.05 = \$3941.05\).