Anonymous asked:
#15 p.773 Blue Book 2nd editionUgh. This question is the WORST (besides #18 in the same section). If you try to get fancy and just do 4 x 4 x 3, you don’t get the right answer. That’s because the order does not matter for the trainees. To get questions like this right, for sure, just list the possibilities instead of trying to calculate them. I promise it won’t take long.
Say your trainees are 1, 2, 3, and 4. Say your experienced plumbers are A, B, C, and D.
A12
A13
A14
A23
A24
A34
Bam. That’s all the combinations that go with experienced plumber A. Six. Didn’t take long at all. There will be six more for B, six more for C, and six more for D. Total: 24.
For practice with counting questions, go here.