Latest Elitmus Aptitude Question SOLUTION: if a, a+2, a+4 are prime numbers ,then the number of possible solutions for a is- a. 1 b.2 c. 3 d. more than 3

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(#M40052221) ELITMUS Numerical Ability question number system Keep an EYE

if a, a+2, a+4 are prime numbers ,then the number of possible solutions for a is-
a. 1 b.2 c. 3 d. more than 3

Asked In Elitmus jitu (9 years ago)

Unsolved Read Solution (39)

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Read Solution (39) :

Rini  (9 years ago)

only on solution exist which is 3

Is this solution Helpfull? Yes (32) | No (7)  

Tanay Kumar  (9 years ago)

option:-a
3,5,7(only 1 case)

Is this solution Helpfull? Yes (28) | No (8)  

Akhil Dhawan  (9 years ago)

option ( b )
put a= 1, the combination will be 1,3,5
put a=3
the combination will be 3, 5,7
which r prime no.

Is this solution Helpfull? Yes (13) | No (49)  

lokesh kumar vyas  (9 years ago)

more than 3 is right answer
because
put a=1 no 1,3,5
put a=5 no 5,7,11
put a=11 no 11,13,17
put a=17 no 17,19,23

Is this solution Helpfull? Yes (9) | No (104)  

Manisha Barik  (9 years ago)

Ans.1
(3,5,7)

Is this solution Helpfull? Yes (7) | No (3)  

Anoop Tiwari  (9 years ago)

ans is a)1 only a=3 will satisfy the condition of prime number.i.e, 3,5,7

Is this solution Helpfull? Yes (7) | No (4)  

Kiran R h  (9 years ago)

Ans= 1 becuz 1 is not a prime no .. so 3 , 5 ,7

Is this solution Helpfull? Yes (7) | No (3)  

shashikant kumar  (9 years ago)

only one solution,put a=3 then we get 3,5,7

Is this solution Helpfull? Yes (4) | No   

Dipesh Malkar  (9 years ago)

only for a=1 or 3 so the answer is b

Is this solution Helpfull? Yes (4) | No (5)  

ankur kumar  (9 years ago)

option a=1
it will take only one value 3
3
3+2=5
3+4=7
(3,5,7) so answr is only one value will take

Is this solution Helpfull? Yes (4) | No   

pratap kumar sahoo  (9 years ago)

a a+2 a+4
put a=1,2,3....

at a=1: 1,3,5 (But 1 is not prime number it is a unique number )
at a=3: 3,5,7
at a=5: 5,7,9(Not prime number set)
.....
so,only 1 combination is possible..ans(a)

Is this solution Helpfull? Yes (4) | No   

Ramesh sai  (9 years ago)

@Akhil Dhawan
1 is not a prime number => a=3 is the only possible solution

Is this solution Helpfull? Yes (3) | No   

abhishek kumar  (9 years ago)

a=1 then 1,3,5
a=3 then 3,5,7
so the ans. will be (b).

Is this solution Helpfull? Yes (2) | No (11)  

swati priya  (9 years ago)

only one solution i.e., 3
a=3
a+2=5
a+4=7

Is this solution Helpfull? Yes (2) | No   

Dinni  (9 years ago)

Ans. is 1
Since 1 is not a prime no.
So take a=3 then a,a+2,a+4 = 3,5,7.

Is this solution Helpfull? Yes (2) | No   

ANUJ KUMAR TRIPATHI  (8 years ago)

more than 3
5, 5+2=7 ,7+4=11
11,11+2=13,13+4=17
17,17+2=19,19+4=23,
41,41+2=43,43+4=47

Is this solution Helpfull? Yes (2) | No (7)  

Nitish Kumar Dubey  (9 years ago)

MORE THAN 3

If a=1, 1,3,5
If a=3, 3,5,7
If a=5, 5,7,9
-----------------
------------------
IF a=k, then .......

Is this solution Helpfull? Yes (1) | No (13)  

Asmita  (8 years ago)

let value of a = 3
then we get 3,5,7 which is prime so the possible solutns of a will be 3

Is this solution Helpfull? Yes (1) | No (1)  

Mangesh Bansode  (9 years ago)

option a is correct as a=3 gives 3,5,7

Is this solution Helpfull? Yes | No (1)  

rameswarappa  (9 years ago)

if a=1
the combinations will be (1,3,5)
if a=3
the combinations are(3,5,7)

Is this solution Helpfull? Yes | No (4)  

Mogili Ramana  (9 years ago)

a.1 bcz if a=3 then only a,a+2,a+4 exist

Is this solution Helpfull? Yes | No   

naidu  (9 years ago)

Answer would be 3

the possible combinatins are:
5,7,11
11,13.17
and
17,19,23

Is this solution Helpfull? Yes | No (4)  

AVNEESH AGRAWAL  (9 years ago)

only one solution which is 3 , as there is only one possible combination 3,5,7

Is this solution Helpfull? Yes | No   

Neelesh Kumar  (9 years ago)

Que is that how many possible value of a, which satisfy the condition...
a, a+2, a+4 will be prime.
if we take a=3
3, 5, 7 will be primes
if we take a=37
37, 39, 41 also primes values
then possible solution values of a is 3,37.
ans will be: b). 2

Is this solution Helpfull? Yes | No (8)  

Dinni  (9 years ago)

Ans. is 2
If a=3 => 3,5,7
If a=11 => 11,13,17

Is this solution Helpfull? Yes | No (4)  

chhaya  (8 years ago)

only solution exist which is 3 bcz prime no (expect 2,3 )are of form 6M+-1 if v take a =6M+1 ,a+2 will be 6M+3 which is divisible by 3 and if v take a=6M-1 ,a+4 will be 6M+3 which is divisible by 3 so only solution is 3,5,7 only one combo

Is this solution Helpfull? Yes | No   

Suman Kumar  (8 years ago)

ans is : c
a = 1 : (1,3,5)//////
a = 3 : (3,5,7)//////
a=41 :(41,43,47)//////////

Is this solution Helpfull? Yes | No (5)  

RAKESH RANJAN  (8 years ago)

only 1 soln is possible when we put a=3 then we get only 3,5,7

Is this solution Helpfull? Yes | No   

Ashish Kumar Dwivedi  (8 years ago)

three cases are possible
a=1,3,5

Is this solution Helpfull? Yes | No (2)  

Abhinav Kumar Roy  (8 years ago)

lage raho dosto infinity hoga....

Is this solution Helpfull? Yes | No (5)  

ANKIT SINGH  (8 years ago)

option a..
bcoz 1 is not prime n 3 is the lone no. satisfying the condition..
so 3.

Is this solution Helpfull? Yes | No (1)  

Sandeep  (8 years ago)

option:-B bcoz....when put
a=3 3,3+2=5,3+4=7
so , 3,5,7
a=17 17, 17+2=19 ,17+4=23
so, 17,19,23

Is this solution Helpfull? Yes | No (4)  

Naveen Tiwari  (8 years ago)

Only one solution which is a=3..3,5,7
@akhil dhawan Bandhu 1 is not prime number

Is this solution Helpfull? Yes | No   

Agniv Chatterjee  (8 years ago)

Answer is more than 3...
1 is not a prime number nor a composite number,a number which is divisible itself and 1 is a prime number..
hence,
Put a =5,11,17,41....

Is this solution Helpfull? Yes | No   

vijay  (8 years ago)

option d
a=1 then 1,3,5
a=3 then 3,5,7
.........

Is this solution Helpfull? Yes | No (1)  

shilpa  (7 years ago)

a=1,3,11
if a=5
5,7,9 nt prime

Is this solution Helpfull? Yes | No   

VIVEK RAWAT  (7 years ago)

1,3 satisfy only so ans is 2

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Birendra Vikram Singh  (7 years ago)

b.2 solution
3 and 11

Is this solution Helpfull? Yes | No   

Susmeeta Sau  (6 years ago)

The only even prime number is 2. If a = 2, then a+2 = 4, and it is composite. So a = 2 is not a solution. Other than two, we have only odd numbers that can be suited to a. If a is odd, then either ‘a’ or ‘a + 2’ or ‘a + 4’ is definitely a multiple of 3. (3 consecutive numbers/3 consecutive odd numbers/3 consecutive even numbers will have always a multiple of 3, and their sum will always be a multiple of 3).

So, we have the only option left with us as a = 3. If a = 3, then we have a + 2 = 5 and a + 4 = 7, and all these numbers are prime. So, we have only 1 solution.

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