What is the next number of the following sequence 21,77,165,285,......

Himanshu Kumar Gupta   10 years AGO

77-21=56
165-77=88
285-165=120
now, 88-56=32
120-88=32
so the difference between the next no. and 285 must be 120+32=152
therefore the no. is 285+152=437

Like? Yes (9) | No (1)  

Madhu pericherla   10 years AGO

(4n+3)(4n+7)
take n=0,1,2,3..
so ans is 437

Like? Yes (6) | No   

Rats   10 years AGO

21(+56)=77
77(+88)=165
165(+120)=285
Now check the addition sequence
56(+32)=88
88(+32)=120
So next addition
120+32=152
So the next term in series
285+152=437....Ans

Like? Yes (7) | No (3)  

sanjay kumar saha   10 years AGO

21 77 165 285 437

56 88 120 152
32 32 32

Like? Yes (4) | No   

FRANKLIN VIJAY   10 years AGO

(4n+3)(4n+7)
n=0,1,2,3,4,...

Like? Yes (3) | No   

ABHISHEK KUMAR MISHRA   10 years AGO

77-21=56
165-77=88
285-165=120
here difference 56,88,120 are in A.P and common difference is 32 so next term will be 120+32=152
so our required term is 285+152=437 Answer

Like? Yes (3) | No (1)  

Deepak Sharma   10 years AGO

5^2-4=21
9^2-4=77
13^2-4=165
17^2-4=285
so next will be
21^2-4=437
therefore option 2 is correct.

Like? Yes (2) | No   

Jigyasa Kumar   10 years AGO

on keeping the values in(4n+3)(4n+7)
where,
n=0,1,2,3....
we get the following series

Like? Yes (4) | No (2)  

Aarush Singh   10 years AGO

(4n+3)(4n+7)
n=0,1,2,3....

Like? Yes (4) | No (2)  

sujeet kumar keshri   10 years AGO

4^2+5=21
8^2+13=77
12^2+21=165
16^2+29=285
20^2+37=437

Like? Yes (3) | No (1)  

devendra kumar gond   10 years AGO

the series comes by following the pattern
21 77 165 285 437
56 88 120 152
32 32 32

Like? Yes (4) | No (2)  

rathinaganesh   10 years AGO

(4n+3)(4n+7)
substitute n=0;
21
substitute n=1;
77
...substitute n=4;
437

Like? Yes (2) | No   

sivaraman   10 years AGO

77-21=56, 165-77=88, 285-165=120
so difference is between this differnces 32

so 152+285=437

Like? Yes (2) | No   

IFFAT IRAM   10 years AGO

21=5^2-4
77=9^2-4
165=13^2-4
285=17^2-4
next number=21^2-4=437
option 2

Like? Yes (2) | No   

Tanvi   10 years AGO

3*7=21 (7-3=4)
7*11=77 (11-7=4)
11*15=165 (15-11=4)
15*19=285 (19-15=4)
19*23=437 (23-19=4)

Like? Yes (2) | No   

Udhaya kumar   10 years AGO

It is the sequence of
PREV.NO+(8N)
N=n+4
where N=7,11,15,19 respectively...
285+(8*(15+4))=437.........

Like? Yes (2) | No   

Niraj   10 years AGO

3 * 7 = 21
7 * 11 = 77
11 * 15 = 165
15 * 19 = 285
19 * 23 = 437

Like? Yes (3) | No (2)  

Anil Kumar Bharti   10 years AGO

Exp:
21,77,165,285,...
first diff. are: 56, 88, 120, .....
second diff are: 32, 32, 32....
So first next diff will be: 120+32=152
and next term will be: 285+152 = 437 Ans
Or,
5^2-4=21
9^2-4=77
13^2-4=165
17^2-4=285
21^2-4=437 Ans

Like? Yes (2) | No (1)  

Parthiban C   10 years AGO

diff of the series is 56,88,120....
so 32 is added constantly
then 120+32=152
now add it to 285=285+152=437=ans.....:)

Like? Yes (1) | No   

Mayuresh Srivastava   10 years AGO

21 77 165 285 437
56 88 120 152
32 32 32

Like? Yes (1) | No   

Abhishek Mishra   10 years AGO

Difference of difference is 32.
e.g.->77-21=56
->165-77=88
Now difference of difference is =88-56=32.
so following this we can guess next number that is->437

Like? Yes (1) | No   

Suman Saurabh   10 years AGO

given series,
21 77 165 285 ?
56 88 120 152
Hence next number of series = 285+152=437

Like? Yes (1) | No   

abhishek   10 years AGO

diff b/w 21&77 is 56,165&77 is 88,285 &165 is 120
56+32=88,88+32=120 derfore 120+32=152 so 285+152=437

Like? Yes (1) | No   

Devendra Marghade   10 years AGO

5^2-4=21
9^2-4=77
13^2-4=165
17^2-4=285
21^2-4=437

Like? Yes (1) | No   

raju kumar sah   10 years AGO

21,77,165,285,....
21+56=77....56=7*8
77+88=165....88=11*8
165+120=285...120=15*8 then next no is
285+19*8=437

Like? Yes (1) | No   

Rhema   10 years AGO

3*7=21
7*11=77
11*15=165
15*19=285
19*23=437

Like? Yes (1) | No   

Asiya Shazmi   10 years AGO

multiplying the alternate odd numbers.
3*7=21
7*11=77
11*15=165
15*19=285
19*23=437

Like? Yes (1) | No   

Abhishek Kumar   10 years AGO

77-21=56 i.e 8*7
165-77=88 i.e 8*11
285-165=120 i.e 8*15
so,according to that when we add 8*19=152 to 285 ,we get the next no. of this series.
therefore the ans is 285+152=437 (2)is correct

Like? Yes (1) | No   

Rajeswaran   10 years AGO

77-21=56 165-77=88 285-165=120

88-56=32 120-88=32
So, now we know the difference is 32
so 120+32=152

Therefore 285+152=437

Like? Yes (2) | No (1)  

Rama Devi Perumalla   10 years AGO

differnces remain constant in the second stage i.e;
in first stage the diffrences are 56,88,120
the difference of differences is (88-56),(120-88)=32,32
so the next differnce in first stage will be 120+32=152.so the sequence no. is 152+285=437

Like? Yes (1) | No   

prayas goel   10 years AGO

See 77-21=56
165-77=88
285-165=120
Now 88-56=32
and 120-88=32
so next term will be (285+120+32=437)

Like? Yes (1) | No   

sugyani dalai   10 years AGO

21 77 165 285 437
56 88 120 152
32 32 32 32

Like? Yes (1) | No   

abhik k. dey   10 years AGO

difference of this 4 numbers are 56, 88, 120, 152,
& difference of different if 32, 32, ...
so next number will be 32+120+285=437

Like? Yes (1) | No   

saranya   10 years AGO

difference between 21 & 77 is 56,77 & 165 is 88,165 & 285 is 120.
then find the difference between all the differences i.e 88 & 56 is 32
120 & 88 is 32
so the next number should also have the same difference so 120+32=152
so add 152 to 285 which is 437

Like? Yes (1) | No   

Rupalika senapati   10 years AGO

(4)2+5=21
(8)2+13=77
(12)2+21=165
(16)2+29=285
(20)2+37=437

Like? Yes (1) | No   

Jacky shevkani   10 years AGO

the differences between the neighbouring terms of the given sequence are in AP with d=32.
so the next term is 437

Like? Yes (1) | No   

mohit tembhre   10 years AGO

in this series the numbers are increase with the diffrence of last two numbers

Like? Yes (1) | No   

rohit kumar   10 years AGO

this series is based on difference b/w two numbers:-
77-21=56(2nd-1st)
165-77=88(3rd-2nd)
285-165=120(4th-3rd)

when we add 32 to 56 i.e
56+32=88
similar way,
88+32=120
120+32=152

so we add 152 to 285 i.e
next term term will be
285+152=437

Like? Yes (1) | No   

yarasi meena   10 years AGO

21,77,165,285....
the difference b/w two numbers is 56 88 120
the difference b/w these numbers is 32 32 and the next diff also 32 i.e the second serious becomes 56 88 120 152
and the final answer is 21,77,165,285,437
so the answer is 437

Like? Yes (1) | No   

Harshit Singh   10 years AGO

difference between the numbers are
21-77=56
77-165=88
165-285=120
and difference between the
120-88-56 is 32
so by adding 32 in 120 and then adding it to th 285.
we get the next number 437

Like? Yes (1) | No   

Shuvankar Ghosh   10 years AGO

using triangular rule

Like? Yes (1) | No   

mohan lal garg   10 years AGO

19*23=437

Like? Yes (2) | No (1)  

Manoji Kumar   10 years AGO

21,77,165,285,_437_
the difference is 56 ,88, 120,_152__
32, 32, 32

Like? Yes (1) | No   

Totan Shit   10 years AGO

21=3*7
77=7*11
165=3*5*11
285=3*5*19
77/21=7*11/3*7=11/3
165/77=3*5*11/7*11=15/7
285/165=3*5*19/3*5*11=19/11
then 11/3,15/7,19/11,23/15
so next number will be 285*23/15=437

Like? Yes (1) | No   

sowmya   10 years AGO

calculate difference of two consecutive no.s so ans is 437

Like? Yes (1) | No   

MUKESH KUMAR   10 years AGO

21 = (3)(7), 77 = (7)(11), 165 = (11)(15), 285 = (15)(19), 437 = (19)(23)

Like? Yes (1) | No   

SHIVANI PRAKASH   10 years AGO

21, 77, 165, 285
diff: 56 88 120
diff: 32 32
120+32=152
152+285=437

Like? Yes (1) | No   

VIDYASAGAR   10 years AGO

every number in the series is to be added with the multiples of 32

Like? Yes (1) | No   

sairam   10 years AGO

77-21=56
165-77=88
285-165=120
88-56=32
120-88=32
so 120+32=152
285+152=437

Like? Yes (1) | No   

HardikDungrani   10 years AGO

Here,
77-21=56
165-77=88
285-165=120
Now,difference b/w 56 ,88 and 120 is 32.
So, 56+32=88,88+32=120,120+32=152.
The next number in seq. is 285+152=437.
437

Like? Yes (1) | No   

Neha Rani   10 years AGO

4*4+5=21
8*8+13=77
12*12+21=165
16*16+29=285
so,20*20+37=437

Like? Yes (1) | No   

PALLE MOUNICA   10 years AGO

19*23 = 437

Like? Yes (1) | No   

Mariappan   10 years AGO

The Sequence is of the Form (4n+3)(4n+7)

Like? Yes (1) | No   

ravi singh   10 years AGO

answer is 437

21 + 8*(7+4*0) =77

77 + 8*(7+4*1) = 165

165 + 8*(7+4*2) =285

285 + 8*(7+4*3) =437

hence option is option 2

Like? Yes (1) | No   

Muhammad Nadeem Haider Naseem   10 years AGO

(4n+3)(4n+7)
for n=0,1,2,3,...,

Like? Yes (1) | No   

ponprakash   10 years AGO

5^2-4=21
9^2-4=77
13^2-4=165
17^2-4=285
(i.e) 21^2-4=437
ans : 2)437

Like? Yes (1) | No   

HARIHARAN S   10 years AGO

21 77 165 285 437
56 88 120 152
32 32 32

Like? Yes (1) | No   

Raunak MAnchanda   10 years AGO

21=5^2-2^2
77=9^2-2^2
165=13^2-2^2
285=17^2-2^2
Difference between the numbers =4
Thus next number will be 21^2-2^2=437

Like? Yes (2) | No (1)  

Yallapu Uday tarun kumar   10 years AGO

21 77 165 285 ..
56 88 120 ...
32 32 ....
next no=285+120+32=437

Like? Yes (1) | No   

Raju   10 years AGO

77-21=56----7x8=56, 56+21=77 2nd term
165-77=88---11x8=88, 88+77=165 3rd term
285-165=120---15x8=120, 120+165=285 4th term
437-152=285---19x8=152, 152+285=437 5th term(result)
so Answ should be B

Like? Yes (1) | No   

Ezhilarasi   10 years AGO

21=(3)(3+4)=3*7
77=(7)(7+4)=7*11
165=(11)(11+4)=11*15
285=(15)(15+4)=15*19
ans=(19)(19+4)=19*23=437

Like? Yes (1) | No   

ShAg   10 years AGO

77-21=56
165-77=88
285-165=120
now,
88-56=32
120-88=32
so, 120+32=152
285+152=437

Like? Yes (1) | No   

Alok Gupta   10 years AGO

77-21=56,165-277=88,285-165=120 diff is 32 to next number 88-56=32 ,

Like? Yes (1) | No   

sudipta sadhukhan   10 years AGO

5²-4=21
(5+4)²-4=77
(9+4)²-4=165
17²-4=285
21²-4=437

Like? Yes (1) | No   

KRISHNA CHOUDHARY   10 years AGO

3*7,7*11,11*15,15*19,19*23=437

Like? Yes (1) | No   

richa ahuja   10 years AGO

the difference are in ap

Like? Yes (1) | No   

Gopichand Godichala   10 years AGO

actually this series can be represented in the below way....

21...77...165....285.....437(ans)
+56 +88 +120 +152
+32 +32 +32

the first level difference between values...
second level shows the constant 32 value increased...........

Like? Yes (1) | No   

Murugaraj   10 years AGO

77-21=56
165-77=88
88-56=32
similarly the difference should come as 32 b/w two succive results
437-285=152
152-130=32
so ans is 437

Like? Yes (1) | No   

sunil   10 years AGO

21=5^2-4
77=9^2-4
165=13^2-4
285=17^2-4

and the sequence is 5,9,13,17,21
so,21^2-4=437

Like? Yes (1) | No   

mageshrani   10 years AGO

21 = (3)(7), 77 = (7)(11), 165 = (11)(15), 285 = (15)(19), 437 = (19)(23)...

Like? Yes (1) | No   

cp   10 years AGO

77-21=56
165-77=88, 88-56=32
285-165=120,
therefore 120+32=152
285+152=437

Like? Yes (1) | No   

Dilip B Gauswami   10 years AGO

77-21=56,
165-77=88,
285-165=120,
x-285=152
x=437

Like? Yes (1) | No   

kumar sundram   10 years AGO

3x7=21;
7x11=77;
11x15=165;
15x19=285;
so,
19x23=437

Like? Yes (1) | No   

Ch Kumaraswamy   10 years AGO

5^2-4=21,
add 4 to the 5
9^2-4=77,

13^2-4=165,
17^2-4=285,
next no wiil be
21^-4=437.

ans=437

Like? Yes (1) | No   

soundarapandi   10 years AGO

5*5=25-4=21
9*9=81-4=77
13*13=169-4=165
17*17=289-4=285
21*21=441-4=437

Like? Yes (1) | No   

Preeti Barman   10 years AGO

77-21=56;
165-77=88;
285-165=120;
then...
88-56=32
120-88=32...
therefore the last term will be..32+120+285=437

Like? Yes (1) | No   

Bingumalla Abinay   10 years AGO

77-21=56 (7*8)
165-77=88 (11*8)
285-165=120 (15*8)

7,11,15,?
?=15+4=19

19*8=152
so next no is 152+285=437

Like? Yes (1) | No (1)  

Kumar Ankit   10 years AGO

Given series 21,77,165,285
77-21=56
165-77=88
285-165=120
Now here another series which are 56,88,120
88-56=32
120-88=32
i.e next one is 120+32=152
Now come to original series
285+152=437

Like? Yes (2) | No (2)  

Gourav Rusiya   10 years AGO

Logic is 77-21=56
165-77=88
and 88-56=32,hence 32 is added
Therefore,120+32=152
and 285+152=437

Like? Yes (1) | No (1)  

Rashmi bharti   10 years AGO

21,77,165,285,...Ans-437
Difference between every term again differ by 32.So
77-21=56,165-77=88,285-165=120
Now all these term differ by 32
88-56=32,120-88=32
So next term would increase by 152 i.e, 285+152=437.

Like? Yes (1) | No (1)  

SANTHANAM   10 years AGO

5*5=25-4=21;
9*9=81-4=77;
13*13=169-4=165;
17*17=289-4=285;
similarly,
19*19=441-4=437;

Like? Yes (4) | No (6)