Find the next number of following sequence 1/2,2/5,3/9,5/17,7/33,.......

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18 Feb 2013 Number Problem

Find the next number of following sequence
1/2,2/5,3/9,5/17,7/33,.......

OPtion

1) 9/43
2) 11/43
3) 13/65
4) 11/65
5) 15/69
6) 17/73
7) 15/129
8) 11/76
9) 13/85
10) None of these

Solution

1/2 = 1/2
2/2^2+1 = 2/5
3/2^3+1 =3/9
5/2^4+1 = 5/17
7/2^5+1 = 7/33
11/2^6+1 = 11/65
option 4

Correct Option: 4 Best Solution (5)

Rats   11 years AGO

Numerators are prime numbers i.e. 2,3,5,7,11
Denominators are 5,9(5+4),17(9+8),33(17+16),65(33+32)
So next terms is 11/65

Like? Yes (6) | No (1)  

Ashita Kaushik   11 years AGO

in this series the numerator are the prime numbers starting from 1 amd so the next number in the series will be 11 and the next number in the denominator will be 65 with a difference of 32 from the previous number in the denominator..so the corect answer is option number 4 which is 11/65

Like? Yes (2) | No (1)  

Navakanth   11 years AGO

din:2^n +1
put n=0,1,2....
num:prime nos
1,2,3,5,7,11.....
so ans:11/65

Like? Yes (2) | No (1)  

Rohit Seth   11 years AGO

NUMRATR ARE PRIME NO. SO AFTR 7 NXT PRIME IS= 11

DENOMNATR ARE IN SEQ. LIKE- 2,2^2+1,2^3+1,2^4+1,2^5+1, SO NXT TRM IS 2^6+1=65

Like? Yes (2) | No (1)  

jitendra singh   11 years AGO

1,2,3,5,7,11
2,5,9,17,33,65

Like? Yes (2) | No (2)