Quantitative Aptitude: Number Series Set 110

Directions(1-10): Find the missing term '?' of the following number series.

1. 11,6,7,12,?,67.5
   15
   20
   18
   22
   26
   Option E
   *0.5+0.5
   *1+1
   *1.5+1.5
   *2+2
   *2.5+2.5
   ? = 26
   
   
    



2. 7,?,210,840,2520,5040
   38
   33
   42
   30
   48
   Option C
   *6,*5,*4,*3,*2
   ? = 42
   
   
    



3. 5,18,?,83,135,200
   46
   39
   32
   34
   44
   Option E
   +13*1,+13*2,+13*3,+13*4,+13*5
   ? = 44
   
   
    



4. 23,27,35,?,63,83
   40
   35
   30
   47
   45
   Option D
   +4,+8,+12,+16,+20
   ? = 47
   
   
    



5. 254,126,62,?,14,6
   28
   25
   20
   30
   37
   Option D
   /2-1, /2-1, /2-1, /2-1, /2-1
   ? = 30
   
   
    



6. 216,221,228,239,?,269
   225
   220
   252
   230
   215
   Option C
   +5,+7,+11,+13,+17
   ? = 252
   
   
    



7. 125,124,?,111,95,70
   100
   120
   142
   135
   125
   Option B
   -1,-4,-9,-16,-25
   ? = 120
   
   
    



8. 56,57,49,76,?,137
   14
   12
   20
   19
   16
   Option B
   +1^3,-2^3,+3^3,-4^3,+5^3
   ? = 12
   
   
    



9. 5,17,31,47,65,?
   74
   80
   70
   85
   88
   Option D
   +12,+14,+16,+18,+20
   ? = 85
   
   
    



10. 15,24,18,21,?,18
    21
    10
    13
    15
    27
    Option A
    Add 3 and Subtract 3 alternatively
    ? = 21