The students of a class are to be arranged in rows, starting from numb

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The students of a class are to be arranged in rows, starting from number 1, such that a row can have a maximum of x students, where x is a number to be determined that is greater than 1. If the minimum number of rows required to accommodate all the students is 10, what is the number of students in the class?

(1) If 3 students are shifted from row number 9 to row number 10, both the rows would have an equal number of students.

(2) Had there been 1 student less in the class, the minimum number of rows required would have been 9.

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yashikaaggarwal · Answer

IMO is E.

Statement 1: no information regarding students sitting in row 1 to 8 (insufficient)

Statement 2: one less student. Nothing given regarding how many students are allowed to sit in a row. Maximum could be 100 or 2 (insufficient)

Statement 1&2: no common inference to use to determine no. of students.

So, will go with E

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freedom128 · Answer

Max. no. of students in a row = x
Min. no. of rows required to accommodate all students = 10

2 possible cases: 
(A) No. of students when all 10 rows have x students each = 10x 
(B) No. of students when last (10th) row is partially occupied = 9x + j, where j is no. of students in the last (10th) row.

1) If 3 students are shifted from row number 9 to row number 10, both the rows would have an equal number of students. 
Shifting of students is required to equalize no. of students in Rows 9 and 10. This means that only case (B) is applicable.

No of students in row #9 = x
No of students in row #10 = j
x - 3 = j + 3 --> x = j + 6.

We cannot deduce unique value of both x and j. 
NOT SUFFICIENT

2) Had there been 1 student less in the class, the minimum number of rows required would have been 9. 
This means that there is only one student in last (10th) row. Case (B) is thus applicable and j = 1. However, we cannot deduce unique value of x.
NOT SUFFICIENT

Combined 
x = j + 6; and j = 1
So, x = 7

No. of students when last (10th) row is partially occupied = 9x + j = 64
SUFFICIENT

FINAL ANSWER IS (C)

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exc4libur · Answer

(1) insufic
no info about x

(2) insufic
no info about x

(1/2) sufic
assume 2 rows
if first row = x-3
and second row = 1+3 = 4 = first
then, x-3=4, x=7
each row is 7
total: 10*7+1=71

ans (C)

MayankSingh · Answer

IMO C

Note: students of a class arranged in rows, starting from number 1, 
And Max Capacity = x / Each row
Min rows required= 10

Min rows are required when max possible students in each row.
So , 9 rows full, and 10th row = 1 to x students (say 1<=y<=x)
 Total possible students  = 9x + 1 to 10x

A) x-3 = y +3
x = y+6
But no idea about x & y so not sufficient

B) Total students = T-1 = 9x 
T= 9x + 1
Still no idea about x , so not sufficient

Together
T=9x+1
So , 10th row has 1 student
From A) x - 3 = y+3
x= y+6 = 7
so total student = 9*7+1 = 64

minustark · Answer

The students of a class are to be arranged in rows, starting from number 1, such that a row can have a maximum of x students, where x is a number to be determined that is greater than 1. If the minimum number of rows required to accommodate all the students is 10, what is the number of students in the class?

(1) If 3 students are shifted from row number 9 to row number 10, both the rows would have an equal number of students.

(2) Had there been 1 student less in the class, the minimum number of rows required would have been 9.

The maximum students of the class is 10x and the minimum students of the class can be 10.
1) From this we can infer the value of x is at least 7 (Suppose there was 7 students in row 9 and 1 student in row 10). But no other info was given. Insufficient
2) The minimum number of students in the class was 10. Not sufficient.
Together, we cannot get enough info to find out the number of students in the class. Not sufficient.
E is the answer

monikakumar · Answer

The students of a class are to be arranged in rows, starting from number 1, such that a row can have a maximum of x students, where x is a number to be determined that is greater than 1. If the minimum number of rows required to accommodate all the students is 10, what is the number of students in the class?

(1) If 3 students are shifted from row number 9 to row number 10, both the rows would have an equal number of students.

(2) Had there been 1 student less in the class, the minimum number of rows required would have been 9.

1) X9 can be 7,8,9,10...X10 can be 1,2,3,4
insufficient

2) X value unknown..here it means, X10 has 1 student only
insufficient to find total students

1+2)
so, X10 =1, then X9=7
so 9*7=63+1=64
sufficient

Ans C

TarPhi · Answer

Statement 1:
There are 4 cases

1 originally in R10 + 3 from R9 = 4 students in R10 
Hence Originally in R9 =>7

2 originally in R10 + 3 from R9 = 5 students in R10
Hence Originally in R9 =>8

3 originally in R10 + 3 from R9 = 6 students in R10
Hence Originally in R9 =>9

4 originally in R10 + 3 from R9 = 7 students in R10
Hence Originally in R9 =>10

Statment 2:
Not enough info

Statement 1 & 2 -
Only Case 1 qualifies if you remove the 1 in R10.

Hence C

PietroCavallo · Answer

Your 9x+j is such a big assumption. The text says that each row can have a *maximum* of x students, not that every row will have it no matter what.

The students of a class are to be arranged in rows, starting from numb

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The students of a class are to be arranged in rows, starting from numb

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