If x and y are two positive integers and x + y = 5, then what is the

Question

If x and y are two positive integers and x + y = 5, then what is the probability that x equals 1?

(A) 1/2
(B) 1/3
(C) 1/4
(D) 1/5
(E) 1/6

Archit3110 · Answer

total pairs possible 
( 1,4),(4,1) ; (2,3); (3,2) ; 4 pairs
so x=1 pair possible only 
1/4
IMO C

sanyamjain2408 · Answer

There are 4 possibilities to get sum of positive numbers as 5:
(1,4) (4,1)
(2,3) (3,2)
Ans:-(c) 1/4

Archit3110 · Answer

sanyamjain2408  
any reason why did not consider 0 pair?

sanyamjain2408 · Answer

Archit3110 
Because 0 is a not a positive number.

Posted from my mobile device

Archit3110 · Answer

yes x>0 in this case got it thanks

m1033512 · Answer

IMO C

x can take values 1 to 4

so probab of getting x = 1

is 1/4

Posted from my mobile device

ScottTargetTestPrep · Answer

The options for (x,y) are:

(1,4)

(4,1)

(3,2)

(2,3)

So the probability that x is 1 is 1/4.

Answer: C

BrushMyQuant · Answer

Theory: Probability of Occurrence of and event P(E) is given by

P(E) = Number of Favorable Outcomes / Total Number of Outcomes

Given that x and y are two positive integers and x + y = 5 and we need to find the probability that x equals 1

Let's start by writing all the possible outcomes for x+y = 5, given that both x and y are positive integers. Possible outcomes are

x = 1, y = 4
x = 2, y = 3
x = 3, y = 2
x = 4, y = 1

So,  Total Number of Outcomes = 4 
Number of  Favorable outcomes in which x = 1 is 1  (x = 1, y = 4)

=> Probability (x=1) = (Favorable outcomes in which x = 1) / Total Number of Outcomes =  \frac{1}{4}

So,  Answer will be C .
Hope it helps!

bumpbot · Answer

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If x and y are two positive integers and x + y = 5, then what is the

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If x and y are two positive integers and x + y = 5, then what is the

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