We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
0
145
3
avatar

1) Everyone at the party shook hands with everyone else exactly once. If there were a total of 21 handshakes, how many people were at the party?

 

2) Kathy tossed a coin 8 times and got 3 heads and 5 tails. How many different sequences of results could she have gotten? 

 

Thanks! These are a couple problems that have stumped me and need some help on :)

 May 4, 2019
 #1
avatar+4325 
+1

1. We can use the handshakes formula here...n(n-1) / 2 =21 n(n-1)=42, n=7 people at the party.

 

2. Think of arranging three identical letters with five other identical letters. How many ways are there to do this?

 May 4, 2019
 #2
avatar
0

Thanks!

 May 4, 2019
 #3
avatar+4325 
+1

No problem...and the answer to the second question should be \(\frac{8!}{3!*5!}=\boxed{56}\) different sequences.

tertre  May 4, 2019

25 Online Users

avatar
avatar
avatar