Giant Basketball
(page 162)

(May 2014) First solution, from Katie Hobson in Albany, Oregon!

We are a seventh grade class from Timber Ridge School in Albany, Oregon.

For the Giant Basketball problem they were asking two main questions. The questions were, how many newspapers did you need to make a 3 meter diameter basketball, and how much paint do you need to cover the basketball?

The surface area of one layer, was 282,600 cm. We found that by multiplying 4(3.14)(150 squared). Because there are 6 layers we multiplied it by 6, which was 1,695,600 cm squared. We then multiplied 80(60) and got 4,800 cm squared. We multiplied 80 and 60 because that's the area of one sheet of paper. Then we divided 1,695,600 by 4,800 and got 353.25. Then we divided 353.25 by 16 (because there were 16 sheets of paper in each newspaper) and got 22.078125 and rounded up to 23. We now know that we need 23 newspapers.

The second thing we had to figure out was how much paint we need. The paint is in squared meters and the surface area was in centimeters so we had to divide the surface area by 100. Then we had to figure out how many time 100,000 goes into 282,600 and we got 2.826. We then rounded up to give us 3.

So we need 3 quarts of paint and 23 newspapers.

eeps comments:

Hooray! The first solution for this problem!

So, readers, how did they do? Did they multiply the right things together? Oh, and why, at the end, did they divide by 100,000?

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