M4maths Previous Puzzles

24 Oct 2016 Sequence

Find the missing number of series
6, 60, 210, 504, ?, 1716

OPtion

1) 640
2) 660
3) 870
4) 950
5) 873
6) 687
7) 990
8) 687
9) 931
10)None of these

Solution

Reason- x = 2
series =
(x)^3-x, (2x)^3-2x, (3x)^3-3x,(4x)^3-4x, (5x)^3-5x, (6x)^3-6x
(2)^3-2, (4)^3-4, (6)^3-6, (8)^3-8, (10)^3-10, (12)^3-12
8-2, 64-4, 216-6, 512-8, 1000-10, 1728-12
6, 60, 210, 504, 990, 1716

Option 7)

Correct Option: 7 Best Solution (15)

shubham   8 years AGO

1*2*3=6
3*4*5=60
5*6*7=210
7*8*9=504
9*10*11=990
11*12*13=1716

Like? Yes (12) | No   

anubhav verma   8 years AGO

2 ^3 - 2 = 6
4^3 - 4= 60
6^3 - 6 = 210
8^3-8 = 504
10^3 - 10 = 990
12^3 - 12 = 1716

Like? Yes (4) | No   

Lakshmipathi   8 years AGO

1*2*3=6
3*4*5=60
5*6*7=210
7*8*9=504
9*10*11=990
11*12*13=1716
answer is 990

Like? Yes (3) | No   

Lakshmi Narayanan.k   8 years AGO

6,60,610,504,_,1716
2^3-2=6
4^3-4=60
6^3-6=610
8^3-8=504
10^3-10=990
12^3-12=1716. (990 is the correct answer opt 7)

Like? Yes (1) | No   

Rajesh Durisala   8 years AGO

6= 1*2*3
60 = 3*4*5
210 = 5*6*7
504 = 7*8*9
990 = 9*10*11
1716 = 11*12*13

One more solution
6 = 2*2*2 - 2
60 = 4*4*4 - 4
210 = 6*6*6 - 6
504 = 8*8*8 - 8
990 = 10*10*10 - 10
1716 = 12*12*12 - 12

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Venkatesh kadali   8 years AGO

2^3-2 = 6
4^3-4 = 60
6^3-6 = 210
8^3-8 = 504
10^3-10 = 990
so answer is 990 option 7

Like? Yes (1) | No   

Pragati Rode   8 years AGO

series has following pattern
2^3-2=6,
4^3-4=60,
6^3-6=210,
8^3-8=504,
10^3-10=990,
12^3 - 12=1716
so the option is 7

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G.S.Kantharao   8 years AGO

Pattern is 2*3=6
(2+10)*(3+2)=60
(12+18)*(5+2)=210
(30+26)*(7+2)=504
(56+34)*(9+2)=990
(90+42)*(11+2)=1716
Hence the right choice is 990.
And the right option is 7.

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Vijay Kumar   8 years AGO

(2^3)-2=6
(4^3)-4=60
(6^3)-6=210
(8^3)-8=506
(10^3)-10=990
(12^3)-12=1716.
So,the missing no is 990.

Like? Yes (1) | No   

Nwobi Chibuzor    8 years AGO

Notice that the numbers are all multiples of 6. The format is;
6 × (k + the square of the consecutive odd numbers starting from 1);
K = 0, 1, 10, 35, 84, 165, 286, e.t.c.
6 × [(0+1square)= 1] = 6
6 × [(1+3square)= 10]= 60
6 × [(10+5square)= 35] = 210
6 × [(35+7square)= 84]= 504
6 × [(84+9square)= 165] = 990
6 × [(165+11square)= 286] = 1716
Therefore the missing number is 990
Option 7.

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Nitish kesarwani   8 years AGO

divde series by 6 and then you get series 1,101,35,84,165,286
then substrat with each other we get 1,9,25,49,121
option 7

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Dinesh Sharma   8 years AGO

Use (a^3 - a) where a=2,4,6,8, ... , 2n and n>=1

i.e. (2^3 - 2), (4^3 - 4), (6^3 - 6), (8^3 - 8), (10^3 -10), (12^3 -12), and so on...

i.e. 6, 60, 210, 504, 990, 1214 and so on. Option 7 is correct

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A.P.Singh   8 years AGO

1*2*3=6
3*4*5=60
..
..
9*10*11=990

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sruthi pujari   8 years AGO

6,6*10,6*35,6*84,___,6*286
1,10,35,84,___
Here diff is square numbers 9, 25,49 =>81
84+81=165
6*165=990

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Uls Manikanta   8 years AGO

Series is in the form of n*(n+1)*(n+2), (n+2)*(n+3)*(n+4),....where n=1. So, 9*10*11=990 is our answer

Like? Yes | No (1)