steve writes a paper in 6 hours. if eric helps him write his paper it takes them 4 hours. how long does it take eric to write a paper?

Question

steve writes a paper in 6 hours. if eric helps him write his paper it takes them 4 hours. how long does it take eric to write a paper?

Answer 1

Let x = number of hours it takes for Eric to write the paper alone

 

1/x = portion of paper done per hour by Eric

1/6 = portion of paper done per hour by Steve

1/4 = portion of paper done per hour by both of them

 

1/x + 1/6 = 1/4

 

Multiply through by the LCD, 12x to get 12 + 2x = 3x

 

                                                                  x = 12 hours