At a certain stationery shop, the cost of each ruler is 2.5 times the cost of each sharpener. Anil bought 25 rulers and a certain number of sharpeners. Had he bought as many rulers as the number of...

At a certain stationery shop, the cost of each ruler is
2.5 times the cost of each sharpener. Anil bought
25 rulers and a certain number of sharpeners. Had
he bought as many rulers as the number of
sharpeners that he bought and vice versa, his total
expenditure on the two items would have been
93.75% less. How many sharpeners did he buy?