Question

during a garage sale, mrs.graham makes change with only 2 type of coins. two customers need the same amount of change. one customer receives 8 coins, 3 of which are nickels.the second customer receives 11 coins,7 of which are nickels. which equation could be used to determine c, the value of second coin?

Answer 1

Input data

2 type of coins

Customer 1

8 coins, 3 of which are nickles

Customer 2

11 coins, 7 of which are nickles

Procedure

V = total value

Customer 1

V = (8-3)c + (3)*0.05

Customer 2

V = (11-7)c + (7)*0.05

Now we are going to equal the equations

$\begin{gathered} 5c+3\cdot0.05=4c+7\cdot0.05 \\ 5c-4c=7\cdot0.05-3\cdot0.05 \\ c=4\cdot0.05 \\ c=\text{0}.20 \end{gathered}$

The coin c would be c = 0.20