Answer :
the amount in increase is .... well 428 - 365 = 63.
if we take 365 to be the 100%, what is 63 off of it in percentage?
[tex]\bf \begin{array}{ccll} amount&\%\\ \cline{1-2} 365&100\\ 63&x \end{array}\implies \cfrac{365}{63}=\cfrac{100}{x}\implies 365x=6300 \implies x = \cfrac{6300}{365} \\\\\\ x = \cfrac{1260}{73}\implies x = 17\frac{19}{73}\implies x \approx 17.26[/tex]
Answer:
The expression that describes the percent of increase in the account balance is r = 428/365 - 1
Step-by-step explanation:
1. Let's review the information provided to us to understand better the question and how to solve it.
Initial deposit into a savings account = US$ 365
Final amount = US$ 428
Time = 1 year simple interest because there it's not compounded during this term
2. Which expression describes the percent of increase in the account balance?
Let's recall the formula of the simple interest:
Final amount = Initial deposit * (1 + r * t)
Replacing with the real values, we have:
428 = 365 * (1 + r), given that t = 1 because the time is one year
428/365 = (1 + r)
428/365 - 1 = r
r = 1.173 - 1
r = 0.173 (rounding to two decimal places)
The expression that describes the percent of increase in the account balance is r = 428/365 - 1 and r = 0.173 is the expression that solve for r