+0  
 
0
41
3
avatar

How many distinct sums can be obtained by adding three different numbers from the set {3, 6, 9, ... ,27 , 30}?

 Jun 29, 2021
 #1
avatar
0

There are 10 elements, so the answer is C(10,3) = 120.

 Jun 29, 2021
 #3
avatar
0

 

~ never mind ~

Guest Jun 29, 2021
edited by Guest  Jun 29, 2021
 #2
avatar+120966 
+1

The possible  sums are  all  multiples of  3

 

(18, 21, 24 ......78, 81)   =

 

(81 - 18)  / 3    +  1   =

 

63/3  +  1  =

 

21  +  1  =

 

22 distinct sums

 

 

cool cool cool

 Jun 29, 2021

12 Online Users