Math logic
There are 20 children in the group, each two children have a different name. Alena and John are among them. How many ways can we choose 8 children to be among the selected
A) was John
B) was John and Alena
C) at least one was Alena, John
D) maximum one was Alena, John?
Result
A) was John
B) was John and Alena
C) at least one was Alena, John
D) maximum one was Alena, John?
Result
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