Question

A 120-page book hasp lines to a page. If the number of lines were reduced by three
on each page, the number of pages would need to be increased by 20 to give the same
amount of writing space. How many lines were there on each page originally?

Answer 1

Answer:

Let p = no. of pages originally

:

120p = no. of lines originally

then

140(p-3) = when page lines are reduced by 3, and pages increased by 20

:

Total no. of lines remain the same, therefore the equation is:

140(p-3) = 120p

140p - 420 = 120p

140p - 120p = 420

20p = 420

p = 420%2F20

p = 21 lines per page originally

:

:

Prove this by seeing the total number of lines remain the same.

120*21 = 2520 lines