Answer: There are 7 nickles, 21 dimes and 16 quarters.
Step-by-step explanation:
Since we have given that
Number of coins = 44
Let the number of nickels be 'x'.
Let the number of dimes be '3x'.
Let the number of quarters be
[tex]44-(x+3x)\\\\=44-4x[/tex]
According to question, we get
[tex]0.05x+0.10(3x)+0.25(44-4x)=6.45\\\\0.05x+0.3x+11-x=6.45\\\\-0.65x=6.45-11\\\\-0.65x=-4.55\\\\x=\dfrac{4.55}{0.65}\\\\x=7[/tex]
So, there are 7 nickles,
3x =[tex]3\times 7=21[/tex]
[tex]44-4x=44-4\times 7=44-28=16[/tex]
Hence, there are 7 nickles, 21 dimes and 16 quarters.