Let x represent the number of nickles Jill has,y represent the number of pennies,and z represent the number of dollar bills.
1) 0.05x+0.01y+z=9.96
2) y=x+12
3) x=z+5
subtitute 3) into 2)
y=z+5+12
3)a y=z+17
subtitute 3) & 3)a into 1)
0.05(z+5)+0.01(z+17)+z=9.96
5(z+5)+1(z+17)+100z=996
5z+25+z+17+100z=996
106z+42=996
106z=954
z=9
subtitute z=9 into 3)
x=9+5
x=14
subtitute x=14 into 2)
y=14+12
y=26
Therefore,Jill has 14 nickles,26 pennies,and 9 dollar bills in her bank.
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