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?
<h3><u>Answer:</u></h3>
Charlie saved $ 28
<h3><u>Solution:</u></h3>
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,
y = kx --- eqn 1
Where "k" is the constant of proportionality
<em><u>Last week Charlie saved $32 on his earnings of $512</u></em>
y = 32 and x = 512
Substituting in eqn 1, we get
To find amount of saved money, we will substitute k = 0.0625 and x = 448 in eqn 1
You can see that this sequence is geometric so you need to know the geometric sequence which is and if you plug in every thing you get = which would be which is 316,912,650,057,057,350,374,175,801,344