What number goes into 24 and 100

Can you answer my question? will mark brainiest!

Ahomeowner plans to hang wallpaper on one wall of a bedroom that is 10 feet long if a stripe of wallpaper is 20 inches wide and stripes or hung vertically how many stripes on wall paper with the homeowner required

Simplify (a/b - b/a) times (a - a^2/a+b) a - a^2/a=b is a mixed number