+0  
 
-5
592
1
avatar+73 

#11: What do I have to do? Solve!

 Apr 17, 2019
 #1
avatar+128053 
+3

a. 6  12  18  24

 

Not geometric  because there is not a common ratio between terms

It appears the the common difference is 6

This leads us to believe that  "C" might be correct

Check : 

First term  =  6(1 - 1) +  6  = 6

Second term = 6(2 - 1) + 6 = 6 +6 = 12      yep.....that's the correct one  !!!

 

b.  2   14   98     686

We have a common ratio of  14 / 2  = 7  [ check GM that  98/14  is the same ratio ]

This is geometric

Pretty sure that "A" is correct

First term = 2 (7) ^(1 - 1)  = 2*7^0  = 2

Second term  2(7)^(2 - 1)  = 2*7^1  = 14

Yep.....that's correct, too

 

Well....not much mystery to

 

c. 160  80  40  20

 

Must be "B"

 

 

cool cool cool

 Apr 17, 2019

2 Online Users