5, 20, 45, 80, 125, ................. next number of the sequence will be

Bawa   12 years AGO

5*1^2 =5
5*2^2=20
5*3^2=45
5*4^2=80
5*5^2=125
5*6^2= 5*36=180

Like? Yes (9) | No (1)  

Dr.Dipin Singh   12 years AGO

nth term is given by 5n^2.
as
5=5*(1^2)
20= 5*(2^2)
..
..
5*(6^2) = 5*36=180 .. option 4

Like? Yes (7) | No (1)  

HARMEET KAUR   12 years AGO

Difference of numbers is 15,25,35,45,55...

5+15=20
20+25=45
..
..
80+45=125
next 125+55=180

Like? Yes (5) | No (1)  

anna sai kiran   12 years AGO

5x4=20
5x9=45
5x16=80
5x25=125
5x36=180
multiply 5 with 4,9,16,25,36..(which r squares) to get next sequence no.

Like? Yes (2) | No   

maddali sarika   12 years AGO

the squence number square is multiple with 5 then the no 6square is mutiple with 5 then result is 180

Like? Yes (1) | No   

dileep kumar reddi   12 years AGO

5,20(5+15),45(5+15+25),80(5+15+25+35),125(5+15+25+35+45),(5+15+25+35+45+55)=180

Like? Yes (1) | No   

Shiv Kumar   12 years AGO

5*1+0 = 5
5*3 +5 =20
5*5+20 =45
5*7+45 =80
5*9+80 =125
5*11+125=180

Like? Yes (2) | No (1)  

GAURAV KUMAR SRIVASTAV   12 years AGO

5
5+15=20
20+25=45
45+35=80
80+45=125
125+55=180

Like? Yes (2) | No (1)  

Abhishek Kumar Ramani   12 years AGO

5+15=20
20+25=45
45+35=80
80+45=125
125+55=180

Like? Yes (1) | No   

ENABOTHULA MOUNIKA   12 years AGO

5*2^2=20,5*3^2=45,5*4^2=80,5*5^2=125 similarly,5*6^2=180

Like? Yes (1) | No   

Narayan Regmi   12 years AGO

The increment is 15, 25, 35, 45, 55 and so on

Like? Yes (1) | No   

Mohammed Akram   12 years AGO

5 20 45 80 125 180
(20-5)15 25 35 45 55

Like? Yes (2) | No (1)  

reshma   12 years AGO

5+15=20
20+25=45
45+35=80
80+45=125
125+55=180

Like? Yes (1) | No   

yelleti vishali   12 years AGO

dif b/w digits in sequence is 15,25,35,45 and new no in seris is125+55

Like? Yes (1) | No   

kunal sharma   12 years AGO

The difference sequence is 15, 25, 35, 45, 55
so next number of the sequence 5, 20, 45, 80, 125 , 180

Like? Yes (3) | No (2)  

RajiniRaja S   12 years AGO

5, 20, 45, 80, 125...
this sequence incremented by 15, 25,35,45.. and so 55.. like this..
5(+15) = 20
20(+25) = 45
45(+35) = 80
80(+45) = 125
125(+55) = 180

So the result is 180 Option 4)

Like? Yes (3) | No (3)  

Manikanta   12 years AGO

In given series 5,20,45,80,125,... take 5 common
=> 5 ( 1,4,9,16,25,...) clearly square of natural numbers.
so next numbre will be 6^2 = 36
so answer will be 5(36) = 180

Like? Yes (2) | No (2)  

Rakesh Kumar Kohli   12 years AGO

The nth term of the sequence is 5*n^2 as below:

5*1^2 = 5
5*2^2 = 20
5*3^2 = 45
5*4^2 = 80
5*5^2 = 125
5*6^2 = 180

Like? Yes (1) | No (1)  

battula saideswra rao   12 years AGO

20-5=15;15+10+20=45 simillarly 125-80=45,45+10+125=180

Like? Yes (1) | No (1)  

Priyabrata Sahoo   12 years AGO

1*5,4*5,9*5,16*5,25*5,36*5
4-1=3
9-4=5
16-9=7
25-16=9
36-25=11

Like? Yes (1) | No (1)  

Libin M Ali   12 years AGO

5+15=20
20+25=45
45+35=80
80+45=125
125+55=180

Like? Yes (1) | No (1)  

Naveen Hirani   12 years AGO

5+15=20
20+(15+10)=45
45+(15+10+10)=80
80+(15+10+10+10)=125
125+(15+10+10+10+10)=180
and so on........

Like? Yes (1) | No (1)  

jagdish Tak   12 years AGO

5
5+15=20
20+25=45
45+35=80
80+45=125
125+55=180

Like? Yes (1) | No (1)  

aravindkumar   12 years AGO

because,lets take starting number 5,and do it..
5*4=20
5*9=45
5*16=80
5*25=125..so,lets see intermediate values 4,9,16,25 they are squares of 2,3,4,5...so,next should be square of 6...so
5*36=180

Like? Yes (1) | No (1)  

sonal   12 years AGO

answer is 180
all are divisible by 5 by 1 4 16 25 like this nxt will bw 36(square of 6)
36*5=180

Like? Yes (1) | No (1)  

chiru   12 years AGO

divide each and every one with 5..we get 1,4,9,16,25
Hence the next no. be 36 and ans is 36*5=180

Like? Yes (1) | No (1)  

kamatchi.s   12 years AGO

5*4=20 adding 5 to 4 (5+4 =9)
5*9=45 adding 7 to 9 (7+9=16)
5*16=80 adding 9 to 16(9+16=25)
5*25=125 adding 11 to 25(11+25=36)
5*36=180 and it goes on like this

Like? Yes (1) | No (1)  

bhavesh jain   12 years AGO

5+15= 20
20+25=45
so sequnce off addition fr next will be in 15,25,35,45,55 SO 125+55=180

Like? Yes (1) | No (1)  

kalaiarasan   12 years AGO

Diff b/w number increases by 10
5-20=15
45-20=25
80-45=35
125-80=45
so 125+55=180

Like? Yes (1) | No (1)  

sridhar reddy   12 years AGO

5*1^2=5
5*2^2=20
5*3^2=45
5*4^2=80
5*5^2=125
5*6^2=180.......answer

Like? Yes (1) | No (1)  

Mounika Chowdary   12 years AGO

20-5=15
45-20=25
80-45=35
125-80=45
125+55=180.

Like? Yes (1) | No (1)  

susmit   12 years AGO

1)Differences of given numbers are increasing by 10.
15,25,35,45,... . So the next difference is 55.
Hence the next number is 125+55=180
2)5=5*1, 20=5*4,45=5*9 80=5*16 , 125=5*25.
So all numbers are multiples of 5 by squares of natural numbers.
Hence the nest no. is 5*36=180

Like? Yes (1) | No (2)  

Balakumaran N.A   12 years AGO

sequence increasing by 15,25,35,45,...
so, 125+55 = 180.

Like? Yes (2) | No (3)  

vinay upadhyay   12 years AGO

20-5=15
45-20=25..........hence 125+55=180

Like? Yes (1) | No (2)  

nidhi saini   12 years AGO

20-5=15
45-20=25..........hence 125+55=180

Like? Yes (1) | No (2)  

Niraj   12 years AGO

Common difference between the common difference of these numbers are same.
5---->20---->45---->80---->125---->180
15---->25---->35---->45---->55
10---->10---->10---->10

Like? Yes (1) | No (2)  

manudixit   12 years AGO

Every next term got multiple of square of the place with 5,
series is like
5*1^2,5*2^2,5*3^2,5*4^2,5*5^2,5*6^2,.......

Like? Yes (1) | No (2)  

vignesh waran A   12 years AGO

common differnce increases by 5 15 25 35 45 & 55

Like? Yes (1) | No (2)  

Devendra Marghade   12 years AGO

Series is square of even number+square of its half value 2^2+1^2,4^2+2^2,6^2+3^2,8^2+4^2,10^2+5^2,12^2+6^2

Like? Yes (1) | No (2)  

Mullaji Zubair Dawood   12 years AGO

The Difference Increases as 15,25,35,45,next Should be 55,i.e. 125+55=180,so ans.4

Like? Yes (1) | No (2)  

Browns MN   12 years AGO

The diff of preceeding digits r 15,25...so next num is 125+55=180!!

Like? Yes (1) | No (2)  

R.V.Kranthi Sagar   12 years AGO

add 15,25,35,45,55 etc to get the answer....

Like? Yes (1) | No (2)  

Arka Dyuti Boral   12 years AGO

Difference between first two is 15, next two is 25 similarly the difference will be 55.so 125 + 55 is 180

Like? Yes (2) | No (3)