Answer:
12 boxes of bookmarks and 8 packs of dust covers.
Step-by-step explanation:
Shelley wants to have at least 250 bookmarks and dust covers for her 250 books.
One box of bookmarks contain 24 bookmarks.
One pack of dust cover contain 36 dust covers.
Shelley buys same number of bookmarks and dust covers.
So, we need to find out LCM(Least Common Multiple) of 24 and 36 to come to a common number that can be bought.
LCM of 24 and 36 is 72.
But, at least 250 bookmarks or dust covers have to be bought. So, we need to find a multiple of 72 which is greater than or equal to 250.
Let us consider the Table of 72:
72, 144, 216, 288, 360 .....
For having enough count of bookmarks and dust covers, at least 288 bookmarks and dust covers have to be bought.
Number of boxes of bookmarks bought = [tex]\frac{288}{24} \Rightarrow 12[/tex]
Number of packs of dust covers bought = [tex]\frac{288}{36} \Rightarrow 8[/tex]
12 boxes of bookmarks and 8 packs of dust covers.