SOLUTION: There are 70 coins that equal to $9.25 using quarters, nickels, and dimes. How many of each coin is there?

There are many solutions. Here are all 
the ones that have at least 2 of each 
of the three types of coin:

16 quarters = 16×$0.25 =  $4.00
51 dimes    = 51×$0.10 =  $5.10
 3 nickels  =  3×$0.05 =  $0.15
-----------------------------------------
70 coins               =  $9.25


17 quarters = 17×$0.25 =  $4.25
47 dimes    = 47×$0.10 =  $4.70
 6 nickels  =  6×$0.05 =  $0.30
-----------------------------------------
70 coins               =  $9.25


18 quarters = 18×$0.25 =  $4.50
43 dimes    = 43×$0.10 =  $4.30
 9 nickels  =  9×$0.05 =  $0.45
-----------------------------------------
70 coins               =  $9.25


19 quarters = 19×$0.25 =  $4.75
39 dimes    = 39×$0.10 =  $3.90
12 nickels  = 12×$0.05 =  $0.60
-----------------------------------------
70 coins               =  $9.25


20 quarters = 20×$0.25 =  $5.00
35 dimes    = 35×$0.10 =  $3.50
15 nickels  = 15×$0.05 =  $0.75
-----------------------------------------
70 coins               =  $9.25


21 quarters = 21×$0.25 =  $5.25
31 dimes    = 31×$0.10 =  $3.10
18 nickels  = 18×$0.05 =  $0.90
-----------------------------------------
70 coins               =  $9.25


22 quarters = 22×$0.25 =  $5.50
27 dimes    = 27×$0.10 =  $2.70
21 nickels  = 21×$0.05 =  $1.05
-----------------------------------------
70 coins               =  $9.25


23 quarters = 23×$0.25 =  $5.75
23 dimes    = 23×$0.10 =  $2.30
24 nickels  = 24×$0.05 =  $1.20
-----------------------------------------
70 coins               =  $9.25


24 quarters = 24×$0.25 =  $6.00
19 dimes    = 19×$0.10 =  $1.90
27 nickels  = 27×$0.05 =  $1.35
-----------------------------------------
70 coins               =  $9.25


25 quarters = 25×$0.25 =  $6.25
15 dimes    = 15×$0.10 =  $1.50
30 nickels  = 30×$0.05 =  $1.50
-----------------------------------------
70 coins               =  $9.25


26 quarters = 26×$0.25 =  $6.50
11 dimes    = 11×$0.10 =  $1.10
33 nickels  = 33×$0.05 =  $1.65
-----------------------------------------
70 coins               =  $9.25


27 quarters = 27×$0.25 =  $6.75
 7 dimes    =  7×$0.10 =  $0.70
36 nickels  = 36×$0.05 =  $1.80
-----------------------------------------
70 coins               =  $9.25


28 quarters = 28×$0.25 =  $7.00
 3 dimes    =  3×$0.10 =  $0.30
39 nickels  = 39×$0.05 =  $1.95
-----------------------------------------
70 coins               =  $9.25

Edwin