The amount of money that Charlie saves each week is directly proportional to the amount he earns. Last week Charlie saved $32 on his earnings of $512. At the same rate, how much will Charlie save this week on his earnings of $448?
Charlie saved $ 28
Given that amount of money that Charlie saves each week is directly proportional to the amount he earns
Let y represent of saved money and x represent amount of earned money
Therefore,
[tex]\text{ Amount of money saved each week } $\propto$ amount he earns[/tex]
[tex]y \propto x[/tex]
y = kx --- eqn 1
Where "k" is the constant of proportionality
Last week Charlie saved $32 on his earnings of $512
y = 32 and x = 512
Substituting in eqn 1, we get
[tex]32 = k(512)\\\\k = \frac{32}{512} = 0.0625[/tex]
To find amount of saved money, we will substitute k = 0.0625 and x = 448 in eqn 1
y = 0.0625(448) = 28
Thus charlie saved $ 28
