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freedom128
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Peddi, well done. I think your solution is very efficient (multiple of 3 and range of possible x). But, people tend to overevaluate so as not to miss out any possibilities.

Fatineel, try this question. Good or creative solution (other than posted one) will be given kudo. Also, please kudo if this is good question.
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X+Z=9 is a straight line in 2-D plane, and x,z≥1. Hence x will take all integral values in range (9-1)≥x≥1. You don't have to find all the combinations.

Peddi
Given, 19(x+z)+3y=180, maximum value x+z can take is 9, we know that 3y is a multiple of 3 ,for 3y to be a multiple of 3 ,x+z should be multiple of three remember x+z max value is nine ,so x+z = 3,6,9 , substituting integers which add up to 9 , we get x=1,2,3,4,5,6,7,8 total possible values of x=8 , it took me more than four minutes can anyone suggest shorter method

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I solved it this way,
19x+3y+19z=180
We have to find max value of X so Y and Z should be minimum. If y and z are 1 then eq will be = 19x+22=180
19x=158
We can get 19*8=152. 158-152=6 (multiple of 3)
Hence ans should be 8.
13 is anyways not possible as 19*13 will be greater than 180.
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Prasannathawait
I solved it this way,
19x+3y+19z=180
We have to find max value of X so Y and Z should be minimum. If y and z are 1 then eq will be = 19x+22=180
19x=158
We can get 19*8=152. 158-152=6 (multiple of 3)
Hence ans should be 8.
13 is anyways not possible as 19*13 will be greater than 180.

Hahaha, it is true that maximum value of integer x is 8. But, it doesn't directly translate to 8 nos. of solutions that x can have (1,2,...,8) - though in this question, yes. It could be 4 only (e.g. 2,4,6,8).

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X, Y and Z all are positive integers. X > 0, Y > 0 and Z > 0

Since the point has three lines intersecting each other the angles made sum to 360 deg. Thus,

\(19X + 19X + 19Z + 19Z + 3Y + 3Y = 360\) [since every has equal and opposite angle]

\(38(X + Z) + 6Y = 360\)

 \(Y = \frac{(180 -19(X + Z))}{3}\)
 \(Y = 60 – \frac{19(X + Z)}{3}\)

i.e. the maximum value of \(\frac{19(X + Z)}{3} = 57\) and minimum value of \(\frac{19(X + Z)}{3} = 19\) so that Y remains positive.
 \(Max(X + Z) = 9\) and \(Min(X + Z) = 3\)

But we are concerned with finding maximum values of X so considering \(X + Z = 9\),

\(1 ≤ X ≤ 8\) and \(1 ≤ Z ≤ 8\) complementing X

Hence X can have 8 values.

Answer (D).
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chondro48
Prasannathawait
I solved it this way,
19x+3y+19z=180
We have to find max value of X so Y and Z should be minimum. If y and z are 1 then eq will be = 19x+22=180
19x=158
We can get 19*8=152. 158-152=6 (multiple of 3)
Hence ans should be 8.
13 is anyways not possible as 19*13 will be greater than 180.

Hahaha, it is true that maximum value of integer x is 8. But, it doesn't directly translate to 8 nos. of solutions that x can have (1,2,...,8) - though in this question, yes. It could be 4 only (e.g. 2,4,6,8).

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chondro48 looks like Prasannathawait missed writing down 'multiply it by 2'.
Otherwise it's also good solution condition being Y ≠ 1 which would make X a non integer.

Doesn't saying "13 is anyways not possible as 19*13 will be greater than 180" enough as rightly pointed out by him.
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chondro48
Three lines intersect at point \(O\), creating 6 angles. Three adjacent angles are \(19X, 3Y,\) and \(19Z\). If \(X, Y,\) and \(Z\) are positive integers, how many different values of \(X\) can have?
A. 2
B. 3
C. 5
D. 8
E. 13

Source: All questions I posted are adapted or enhanced from OG or OG Quant.
Kudos for a good or creative solution. Also, give +1 kudos if you think this is a good question.

19X + 3Y + 19Z = 180
Since last digit of 180 is 0, last digit of 19X + 3Y + 19Z must be 0
Y=1; Not feasible
Y=2; Not feasible
Y=3; X + Z = 9; Number of solutions = 8 = {(1,8),(2,7),(3,6),(4,5),(5,4),(6,3),(7,2),(8,1)}; X can have 8 different values = {1,2,3,4,5,6,7,8}
Y=22; X + Z = 6; Number of solutions = 5 = {(1,5),(2,4),(3,3),(4,2),(5,1)}; X can have 5 different values = {1,2,3,4,5}
Y=41; X + Z = 3; Number of solutions = 2 = {(1,2),(2,1)}; X can have 2 different values = {1,2}

Overall X have have different values = {1,2,3,4,5,6,7,8} = 8 different values

IMO D

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