Answer:9 nickels and 19 dimes.
Explanation:
Let
be the number of nickels Kay has.
Let
be the number of dimes Kay has.
Value of
nickel is $
![0.05](https://img.qammunity.org/2020/formulas/mathematics/middle-school/icxt00m71hror8gdpj04cme1eaa9pp7jvv.png)
Value of
nickels is $
![0.05n](https://img.qammunity.org/2020/formulas/mathematics/college/41gtr94ybgo0prywuf5l8a3jcql07d7p0z.png)
Value of
dime is $
![0.1](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7nugsqffc0h60jhyowdqaetziszano31vl.png)
Value of
nickels is $
![0.1dn](https://img.qammunity.org/2020/formulas/mathematics/middle-school/f2jumrw1q58571lvyi66nfqyfn0zeyaclu.png)
Given that Kay has a total of
coins.
So,
...(i)
Given that Kay has a total value of $
![2.35](https://img.qammunity.org/2020/formulas/mathematics/middle-school/mf9rr0end0wklfdhxwwfdxr9ed1pfxoexr.png)
So,
...(ii)
Using (i) and (ii),
![0.05n+0.1(28-n)=2.35\\0.05n+2.8-0.1n=2.35\\2.8-2.35=0.05n\\0.45=0.05n\\n=9](https://img.qammunity.org/2020/formulas/mathematics/middle-school/utl1gfppblftb7py4km8lf8mhxsqg3aonl.png)
![d=28-n=28-9=19](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4hswsgohxrl3x7wywsveuelacnjywoub52.png)