+0  
 
0
70
1
avatar

How many numbers are in the list 147, 144, 141,... 42, 39? 

 

 

 

so this means it skips 2 numbers each time and the numers between 147 and 39 are 119 so would i divide by 3?

 Dec 26, 2018
 #1
avatar+98005 
+1

We have this

 

Last term  =  First Term - 3(N - 1)     where N is the number of terms

 

39 =  147 - 3(N - 1)      simplfy

 

39 = 147 - 3N + 3

 

39 + 150 - 3N       subtract 150 from both sides

 

-111 = -3N     divide both sides by -3

 

37 =  N     (37 terms)

 

 

cool cool cool

 Dec 26, 2018

5 Online Users