Christopher would be able to make 18 scarves.
To solve this problem, we just need to divide 12 by 2/3. To divide 12 by 2/3, we just multiply 12 by 3/2.
This will give us 36 over 2 or just 18.
1. cylinder to cone:
(πr^2h)/((1/3)πr^2h) = 3:1
2. sphere to cylinder:
((4/3)πr^3)/(πr^2h) = 4r:3h
3. cone to sphere:
((1/3)πr^2h)/((4/3)πr^3) = h:4r
4. hemisphere to cylinder:
half the ratio of sphere to cylinder = 2r:3h
