Can someone solve these with a solution so I can check my answer

sorry I don't speak maths

17.

Is the "best guess" the same as the mean?

Google "Select Statistics population mean" . It has a calculator that can help check your stats.

Any solution will be different than yours.

I dont have a clue what that is.sorry I cant help you

1/21 + 2/21 + 3/21 + 4/21 + 5/21 + 6/21 =1.00

😬 I don't understand a single word of that

Ummmm..... C?