Miri counted her money and found that her 25 coins which were nickels, dimes, and quarters were worth $3.20. the number of dimes exceeded the number of nickels by 4. how many coins of each kind did she have?

Nickels = x

dimes = x + 4

quarters = x

Value of coins:

nickel = 5 cents

dime = 10 cents

quarter = 25 cents

5x + 10 (x + 4) + 25x = 3.20

5x + 10x + 40 + 25x = 320

40x = 320 - 40

40x = 280

x = 280/40

x = 7

There are 7 quarters, 7 nickels and 11 dimes.