x, y and z are positive integers. How many different ordered groups of

Question

x, y and z are positive integers. How many different ordered groups of {x, y, z) are possible so that x + y + z = 5?

A. 3
B. 4
C. 5
D. 6
E. 8

Archit3110 · Answer

possible pairs of ( x,y,z) such that x+y+z=5
(1,1,3) ; ( 1,2,2)
1,1,3 can be arranged in 3!/2! ; 3 ways
so can be ( 1,2,2 ) 3 ways
total ways 6 option D

MBAHOUSE · Answer

Permutation with repetition where n = k 
n = number os elements
k = number of places
n = k the order matters
There’s no repetition 
n! In the numerator and the number of repetitions! in the denominator

PyjamaScientist · Answer

There are only two possibilities: 1+1+3 = 5 ,or, 1+2+2=5.
Since, we require ordered pairs, total number of ordered pairs of (1,1,3) & (1,2,2) =  \frac{3!}{2} + \frac{3!}{2} = 3+3 = 6 . Option ( D )

Posted from my mobile device

x, y and z are positive integers. How many different ordered groups of

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

x, y and z are positive integers. How many different ordered groups of

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards