Acollection of dimes and quarters worth $9.25. there are 46 coins in all. find how many of each there are. how many dimes are there?

If all were quarters, the value would be 46*$0.25 = $11.50. The actual value is $2.25 less than that. Replacing a quarter with a dime reduces the value by $0.15, so there must be $2.25/$0.15 = 15 dimes

There are 15 dimes.

The lateral side of a triangular pyramid is a triangle. in order to increase the lateral surface area, the slant height and the height should be altered