Rolls of a particular wallpaper have a repeating pattern every 60 cm of their length. Each roll is
10 m long and 50 cm wide. A wall 2.5 m high and 6.2 m wide is to be papered from ceiling to
floor with single lengths of paper hung vertically (drops).
How many rolls of wallpaper will be needed so that the pattern on each drop matches the next?
(No joins can be made in one vertical drop.)
I know that C is correct but WHY?
Please, help me! Thank you!
... and the ones that won't