4.50=(.25*a)+(.10*b)+(.5*c)

Question

what is a b and c?

Answer 1

Robert is correct about needing more equations to find unique answers for a,b,and c.

An alternate answer might be to simply pick numbers that work and give an answer from that group. The a,b,and c seem to be numbers of quarters, dimes, and nickels respectively.

In such a case, you could choose 18 quarters, no dimes, and no nickels to total $4.50.

So a = 18, b=0, and c=0.

Or try 45 dimes, then a=0, b=45, and c=0.

There are many possible answers using this method, so find one you like!

Answer 2

You have 3 unknowns a, b, and c

And you only have 1 equation. ==>> Can't be done.

 

You need one or more independent equation per unknown.

So here you would need 3 independent equations (or more).