| 24. Basically, you have to list the cubes of integers in order until you find one that is divisible by 12.
2^3 = 8 (not divisible by 12)
3^3 = 27 (not divisible by 12)
4^3 = 64 (not divisible by 12)
5^3 = 125 (not divisible by 12)
6^3 = 216 DING DING DING...divisible by 12
Now, since we are looking for what n is, so we divide 216 by 12 = 18. So the answer is 18.
25. If the spokes extend 1/2 inch into the rim and the hub, then the length of one spoke is the radius of the wheel - the hub radius - the rim radius + 1 (because of the sticking into the hub and rim). So one spoke = 11/2 -1-1+1 = 5.5 - 1 = 4.5
Since there are 5 spokes, the total length of the spokes is 4.5*5 = 22.5 |