Choice 1- if the question can be answered using one of the statements alone, while the other statement is not sufficient to answer the question.
Choice 2- if the question can be answered using each of the statements independently
Choice 3- if both the statements together are needed to answer the question
Choice 4- if both the statements independently or taken together are not sufficient to answer the question

question :
if (a+b)^2=25 and (a-b)^2=1
1)a is prime
2)|a|>2 and a is a natural number

• only 2nd statement is needed,
  by solving eqs.we get
  a=3 or 2 or -3 or -2
  in 2nd statement is given that a is a natural no. so a=2 or 3 & also give that |a|>2 then a=3
• 10 years agoHelpfull: Yes(30) No(1)
• Both statements are needed to answer as:-
  (a+b)^2=25 i.e, a+b=5.....(i)
  (a-b)^2=1 i.e, a-b=1.....(ii)
  from (i) and (ii)[eqn(i)+eqn(ii)]
  2a=6 i.e a=3 which is a prime no
  and|a|>2 and is natural no.
  so both statements together needed to ans this.
  
  
  
• 10 years agoHelpfull: Yes(10) No(8)
• Choice1 is the correct answer because using statement 2 only we can get the answer
  
• 10 years agoHelpfull: Yes(3) No(0)
• Choice 3
  to get the value of "a" we must calculate the value of "b".SO we need both the equation
• 10 years agoHelpfull: Yes(1) No(0)
• From the two equations value of a and b can be:
  3,2
  2,3
  -3,-2
  -2,-3
  
  both numbers are prime so we don't require statement 1
  |a|>2 therefore, a can be 3 or -3
  therefore, values of a and b can be:
  3,2 or,
  -3,-2
  
  Since we cannot find the solution through the above 2 statement
  the answer is "Choice 4" ;-)
  
• 10 years agoHelpfull: Yes(1) No(2)
• Answer will be choice 2.
• 10 years agoHelpfull: Yes(1) No(0)
• both statement are necessary
• 10 years agoHelpfull: Yes(0) No(0)
• Choice 1 is the correct answer.statement 2 is enough to get the answer.
• 10 years agoHelpfull: Yes(0) No(0)
• choice 4 because a=3
  
• 10 years agoHelpfull: Yes(0) No(0)
• ans) choice 3
  solving two equations :- a+b=5 & a-b=1,,, we get a=3 and b=2
  if only 2nd option is considered then there are many nos. greater than 2
  hence we need to consider 1st option also that a is prime..
• 9 years agoHelpfull: Yes(0) No(0)
• using the two given equations we will arrive at 4 equations
  which will yield 4 set of values for (a,b) pair..they are
  
  a=3 , b=2
  a=2 , b=3
  a=-3 ,b=-2
  a=-2 ,b=-3
  
  so if use first statement only that is a is prime and all prime numbers are natural numbers so
  last two negative values are eliminated and among first two a=3 is prime so according to this statement a=3 and b=2 is the answer
  
  now if i use the second statement then a=3 or a=-3 but its also written as a is a natural number so
  a=3 and b=2 is the answer
  
  so the solution can be found using either statement alone
  
• 9 years agoHelpfull: Yes(0) No(1)