Need quick help with these perms/coms questionscheck answers

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The discussion addresses a homework problem involving the selection of a cricket committee from a group of former batsmen and bowlers. For the first part, the total number of ways to select a committee with at least one former batsman is calculated as 70. In the second part, the total ways to select a committee with at least one batsman and one bowler is determined to be 65, derived from subtracting the cases with only bowlers from the total selections. The participants confirm that using the combination formula 8C4 could simplify the calculations. The conversation concludes with a sense of clarity regarding the problem-solving approach.
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[SOLVED] Need quick help with these perms/coms questions..check answers

Homework Statement


A cricket selection committee of 4 members is to be chosen from 5 former batsmen and 3 former bowlers.

In how many ways can this committee be selected so that the committee includes at least

1)One former batsman
2) One batsman and one bowler.


Homework Equations





The Attempt at a Solution



B=Batsman
b=bowlers

1)At least one former batsman

1B 3b=5C1*3C3=5
2B 2b=5C2*3C2=30
3B 1b=5C3*3C1=30
4B 0b=5C4=5

total=70 ways

2) no. of way to select without any restriction=8C4=70

so for at least one B and one b, it is 70-5=65


Also,since in part 1,those are the only ways to make the selection...does that mean I could have just said 8C4 instead of writing out all the ways?
 
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Yes to all of the above, I think.
 
well then...great...! I got confused since all of that was 8 marks
 

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