In a certain marching band formation

Question

In a certain marching band formation, each row of band members has the same number of members, and the number of rows is 1 less than the number of members in a row. How many band members are there in each row?

(1) There is a total of 90 band members.
(2) If each of the members of the last row were assigned to a different row, the row with the least number of members would have 10 members.

Baracuda123 · Answer

It is basically a formation that has 1 row less than the number of members ---> number of rows + 1 = number of members in a row

1) There are 90 members overall - x * (x + 1) = 90 - simply plug in numbers 9 and 10 and voila it is sufficient since there are no alternate solutions. We now know the exact number of rows and members in a row. Alternatively, you could simply use the formula x^2 + x - 90 = 0 and find the solution there.  Sufficient

2) A little tricky wording because it almost seems that there could be only one row with the least number of members (in this case 10). But depending on the number of members there could be more rows with 10 members while other rows have more than 10 (i.e. 11).  Not sufficient

Answer A

stne · Answer

To me it seems something is wrong with statement 2 , if all rows are supposed to have the same number of members how can there be a least row and most row? Something seems odd about statement 2

summer101 · Answer

I thought the answer was D. Because i took the last row members and distributed den equally to each row. Which makes the no. of rows (n-2) and row with the least no. will now have (n+1) and two rows will have (n+2)
But they never said they were equally divided. Alas

mahakmalik · Answer

there is something wrong with statement 2...
As.suppose there are 8 rows and each has 9 members
if we distribute the last row then every other row will have 10 members with 1 member still left....
I think statement is not correct.
if we distribute trhe last remaning member then all rows will have 10 members(least in this case) except one,which will have 11 members.

KarishmaB · Answer

Yes, the question is incorrect. 
Stmnt 1 tells you that there are 9 rows and 10 members in each row. 
Stmnt 2 contradicts the information given in the question stem - number of rows is one less than number of members in each row. If this is true, you cannot distribute more members in fewer rows such that each member is assigned to a different row.

Ignore the question.

Bunuel · Answer

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In a certain marching band formation

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In a certain marching band formation

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