SOLUTION: you have a sheet of cookie dough that is 35 centimeters by thirty centimeters, and a cook cutter seven centimeters in diameter. How many cookies should you cut from the dough if yo

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Question 727772: you have a sheet of cookie dough that is 35 centimeters by thirty centimeters, and a cook cutter seven centimeters in diameter. How many cookies should you cut from the dough if you want to use half the dough
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Using whole number cookie cuttered pieces, you will not be able to use exactly half the dough.

Total area for one layer of dough =35%2A30 cm^2.
One cookie cutter's worth of area = pi%2A%287%2F2%29%5E2 cm^2.
Letting q = the whole number count of cookies to cut with the 7 cm diameter cutter, and to use HALF the dough, %2835%29%2830%29%2F2=q%2Api%2A%287%2F2%29%5E2. Solve for q.

Untreated result: q=13.64 pieces at 7 cm diameter. We do not want a non-integer result. We can use 13 cut pieces to use a little less than half the dough, or we can use 14 cut pieces to use a little more than half the dough. Best answer so far is either 13 or 14 cookie-cutter pieces.