The answer is= there are 126 5p coins
the reason for this is that
-630 is simplified to 5,
-so 1/5 is really 126/630,
(630 divided by 5 is 126)
- and so 2/5 is 126 x 2 =252/630
- there are only 3 parts left, and if 1p has more parts than 5p,
-then 1p takes up 2/5 of the bag
-and 5p takes up 1/5 of the bag
Given that Rolex buys computer disks at a price of 4 for $5 .
That means cost price of 1 disk = 5/4
Given that Rolex sells them at a price of 3 for $5.
That means selling price of 1 disk = 5/3
Profit on 1 disk = selling price - cost price
Profit on 1 disk 
Profit on 1 disk 
Profit on 1 disk 
Profit on 1 disk 
Now we have to find how many disk to be sold to get the profit $100
so we just divide $100 by profit on 1 disk

Hence final answer is 240 disks.
Answer is second option 75cubic cm
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