So if we think of a test tube, it looks sort of like a cylinder. This means that its cross-section would be a circle. To find out how many turns a piece of thread would make around the test tube, we need to find the circumference of the test tube, then divide the length of the string by the circumference.

Step 1) Find the circumference

C = pi x diameter

C = 3.14 x 3

C = 9.42

Step 2) Divide the length of the string by the circumference

90.42 / 9.42 = 9.5987

The string would make approximately 9.60 turns around the test tube.

Hope this helps!! :)

6 0

3 years ago

A cube has a volume of 800 cubic units. the length of the edge of this cube is between which two numbers?

8090 [49]

I set this up as an inequality, $800 \leq s^{3}$ . If you take the cubed root of 800, you get the lower bound of the side length, which is 9.2. Then I just worked my way up until I hit the first number that put me over a volume of 800. That number is 9.29, because 9.28 cubed is 799.1 (not high enough) and 9.29 cubed is 801.8. Therefore, the bounds of the sides exist within a conjunction: $9.2\ \textless \ s\ \textless \ 9.29$ . That's the best I could come up with to help on that one. Wasn't sure if there was another method you were taught at school. I just used common sense more than any rule.

8 0

4 years ago