How many rows and columns were added?

Question

A marching band used to have a rectangular marching formation with 8 columns and 10 rows. An equal number of columns and rows were added to the band's marching formation when 40 new members joined. How many rows and columns were added?

Answer 1

TOTAL NO OF MARCHING PERSONS ARE

8 X10 = 80

Let x no columns and row were added  than toatl no of person will be

(8+x)(10+x)=80+40

by solving the above equation you will find

x=2

that is two columns and two rows are to be added

Answer 2

Row new row and 2 new columns

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