Problems - Hard! ASAP! (1 Viewer)

[michael11]

thankyou very much guys

 

[michael11]

hi guys. Could you help me out again? Thanks.

Question 1

Michelle has three more sisters than brothers. How many more sisters than brothers does her brother Ryan have?

Question 2

Five points are marked on a circle. How many different triangles can be formed by joining any three of those points?

 

[Trev]

Q1.
Just pick an example, I did 3 brothers, 6 sisters and Michelle. Ryan, being a brother means that he has 2 brothers and 7 sisters, so 5 more sisters than brothers. (It will stay the same for situation as long as you use the given fact).

Q2.
You could just use counting techniques since it doesn't specify combinations, just draw in 5 dots and connect them up to make triangles and you will get 6 different triangles.

 

[michael11]

so how do you work out 6 triangles?

 

[Trev]

Well then

 

[michael11]

so which one is right? 6 or 10?

 

[Riviet]

I'm pretty sure it's 10.

 

[SoulSearcher]

Its 10 - I drew it out myself