A box contains 400 coins. of these 10 percent are dimes, 30 percent at nickels and rest are quarters. The amount of money in the box is?

10 percent of 400 is 40 coins so 40 dimes is 4.00 dollars ...

Next 30 percent of 400 is 120 coins ... and 120 nickels is 6.00 dollars

Since 40 percent is what was already used ... 60 percent should be quarters which is 240 coins multiples by 25 is ... : 60.00 dollars so in total its 70