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A room contains 120 pillows. The number of pillows per row is 1 less than twice the number of rows. Find the number of rows and number of pillows per row.

 Nov 27, 2018
edited by Guest  Nov 27, 2018

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 #1
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NOW this question makes sense......we had it posted yesterday as 140 pillows.

 

Number of pillows per row =  (2r-1)       r = number of rows

 

total pillows =     (2r-1)(r) = 120

2r^2-r-120 = 0        Use Quadratic Formula to find   r = 8   ( and -7.5 which we will toss out)

Pillows per row = 2r-1 = 15 pillows/row     8 rows

 Nov 27, 2018
 #1
avatar+20239 
0
Best Answer

NOW this question makes sense......we had it posted yesterday as 140 pillows.

 

Number of pillows per row =  (2r-1)       r = number of rows

 

total pillows =     (2r-1)(r) = 120

2r^2-r-120 = 0        Use Quadratic Formula to find   r = 8   ( and -7.5 which we will toss out)

Pillows per row = 2r-1 = 15 pillows/row     8 rows

ElectricPavlov Nov 27, 2018

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