solve this :-
3,10,21,?,65,133

• 3,10,21,?,65,102,133
  n x (next prime no.)
  1 x 3 = 3;
  2 x 5 = 10;
  3 x 7 = 21;
  4 x 11 = 44;
  5 x 13 = 65;
  6 x 17 = 102;
  7 x 19 = 133;
• 8 years agoHelpfull: Yes(58) No(12)
• Answer is 38.
  2^1+1=3
  2^2+6=10
  2^3+13=21
  2^4+22=38
  2^5+33=65
  And so on.
• 8 years agoHelpfull: Yes(13) No(57)
• why you added 1,6,13,22 and 33.?
• 8 years agoHelpfull: Yes(8) No(7)
• what about 133?
  according to umesh's logic
  2^6+69=133..
  how 69 comes in the series 1,6,13,22,33..??????
• 8 years agoHelpfull: Yes(6) No(0)
• 44
  odd prime number are there in series 3*1=3,5*2=10,7*3=21so 11*4=44
• 8 years agoHelpfull: Yes(3) No(0)
• 21 is answer
  as 3*6+3=21
  10*6+5=65
  21*6+7=133
• 8 years agoHelpfull: Yes(2) No(16)
• answer is 38
  2^1+1=3
  2^2+6=10
  2^3+13=21
  2^4+22=38
• 8 years agoHelpfull: Yes(2) No(2)
• 44, 1*3=3,2*5=10,3*7=21,4*11=44,5*13=65,6*17=102,7*19=133
• 8 years agoHelpfull: Yes(2) No(0)
• 44
  Because it contain odd numbers multiply by the numberic numbers
• 8 years agoHelpfull: Yes(2) No(0)
• 44.............multiplication of numbers with their next prime numbers
  i.e, 1*3=3
  2*5=10
  3*7=21
  4*11=44
  5*13=65
  6*17=102
• 7 years agoHelpfull: Yes(2) No(0)
• The formula
  n(2n+1)
  or
  n^2+n^2+n
  1^2+1^2+1
  2^2+2^2+2
  3^3+3^3+3
• 7 years agoHelpfull: Yes(2) No(0)
• i agree with the answer that Mr.Umesh has given and also i would like to give my explanation for the answer
  as you can see they are all in the increasing orders of 2^x apart from that you cans see the numbers that are added up to the 2^x the differences between the two consecutive numbers are as follow 5,7,9,11 which are odd number series
• 8 years agoHelpfull: Yes(0) No(3)
• The total sum is equal to the sum of AP and GP.
  Sum of AP gives : n/2(2a+(n-1)d)= 216
  since a=20,d=2 and n=8;
  for gp sum is a(r^n-1)/r-1=3279
  since a=3 and n=7,r=3;
  hence total is 3279+216=3495
• 8 years agoHelpfull: Yes(0) No(2)
• 3+3+1=10
  10+10+1=21
  21+21+2=44
  65+65+3=133
• 8 years agoHelpfull: Yes(0) No(8)
• 3,10,21,36,55,65,133
• 7 years agoHelpfull: Yes(0) No(1)
• The numbers represent the odd prime numbers.
  So,
  
  3 * 1 = 3
  5 * 2 = 10
  7 * 3 = 21
  11 * 4 = 44
  13 * 5 = 65
  17 * 6 = 102
  19 * 7 = 133.
  
  So, the missing term is 44.
  And, the series is 3, 10, 21, 44, 65,133
• 7 years agoHelpfull: Yes(0) No(0)
• 3,10,21,?,65,102,133
  1 x 3 = 3;
  2 x 5 = 10;
  3 x 7 = 21;
  4 x 11 = 44;
  5 x 13 = 65;
  6 x 17 = 102;
  7 x 19 = 133;
• 6 years agoHelpfull: Yes(0) No(0)
• 44
  1*3=3
  2*5=10
  3*7=21
  4*11=44
  5*13=65
• 6 years agoHelpfull: Yes(0) No(0)
• 11*4 =44
  44 is answer
• 6 years agoHelpfull: Yes(0) No(0)