Question

At the end of the summer,Caitlin had saved $120 from her summer job.This was her initial deposit into a new savings account at the bank. As the school year starts, Caitlin is going to deposit another $5 each week from her allowance. Is her account balance proportional to the number of weeks of deposits?

Answer 1

Initial saving of Caitlin = $120.

After depositing $120 initially, the saving of each week is $5 from her allowance.

Let us find some total saving of each week for some weeks

For first week total saving is $120 + $5 = $125

For second week total saving is = $125 +$5 = $130.

For second week total saving is = $130 +$5 = $135.

For second week total saving is = $135+ $5 = $140.

For second week total saving is = $140 + $5 = $145.

Now let us check propertions of balance to the number of weeks.

1) First week balance : First week = 125 :1 .

2) Second week balance : Second week = 130 : 2 = 65 : 1

3) Third week balance : Third week = 135 : 3 = 45 : 1.

We can clearly see that proportion of balance to the number of weeks are not same.