What is the next number of the following sequence. 9, 7, 7, 9, 13, ....

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10 Nov 2014 Sequence

What is the next number of the following sequence.
9, 7, 7, 9, 13, ....

OPtion

1) 13
2) 16
3) 7
4) 21
5) 9
6) 14
7) 10
8) 17
9) 18
10)None of these

Solution

3^2 = 9 = 9 (sum of digit)
4^2 = 16 = 7 (Sum of digit)
5^2 = 25 = 7 (Sum of digit)
6^2 = 36 = 9 (Sum of digit)
7^2 = 49 = 13 (Sum of digit)
Similarly
8^2 = 64 = 10 (Sum of digit)

Option 7) 10

Correct Option: 7 Best Solution (6)

santosh kumar patel   10 years AGO

SQUARE(3)=9
SQUARE(4)=16=1+6=7 ;
SQUARE(5)=25=2+5=7 ;
SQUARE(6)=36=3+6=9;
SQUARE(7)=49=4+9=13;
SQUARE(8)=64=6+4=10 ;

Like? Yes (10) | No (1)  

Chirag Ranjan Lahiri   10 years AGO

Each term is: The number plus two, squared, then take the sum of the digits
1st case : 1+2=3 , 9 so 9
2nd case : 2+2=4, 16, 1+6=7 so 7
3rd case : 3+2=5, 25, 5+2=7 so 7
4th case : 4+2=6, 36, 3+6=9 so 9
5th case : 5+2=7, 49, 4+9=13 so 13
hence 6th case : 6+2=8, 64, 6+4=10 so 10 is the answer...

Like? Yes (6) | No (2)  

tirupathi reddy   10 years AGO

(9,7,7,9),(13,10,10,13)
The difference is -2,0,+2
And -3,0,+3

Like? Yes (3) | No (2)  

Gaurav kumar   10 years AGO

because after each successive 2 will come between increasing numbers

Like? Yes (1) | No (2)  

sridhar kumar   10 years AGO

diference should b 3

Like? Yes (1) | No (3)  

Karthick Raja   10 years AGO

3*3*1=9
3+3+1=7
so
3+3+4=10

Like? Yes (1) | No (4)