Calculating Simple Interest Rate on a $2,000 Savings Account

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To calculate the annual simple interest rate for Dylan's $2,000 savings account, the interest earned was $73.93 over a period of 257 days. Using the formula r = I/(pt), where I is the interest, p is the principal, and t is the time in years, the calculation yields an annual interest rate. The attempt at a solution initially led to confusion with the final result of 0.02%, which is incorrect given the interest earned. The correct approach reveals that the calculated interest rate should be significantly higher, as the interest earned exceeds what would be expected from such a low rate. Accurate calculations and proper use of parentheses are crucial for clarity in solving interest rate problems.
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Homework Statement


Dylan received an academic achievement prize of $2,000 from his college. He deposited this money into a savings account on July 15, 2016. If the interest accumulated on the investment when he withdraws the money on March 29, 2017 was $73.93, calculate the annual rate of simple interest that the savings account was providing him.

Round to two decimal places

Homework Equations



r=I/pt
I=prt

The Attempt at a Solution


p=2000
I=73.93
t=257/365

73.93/2000*257/365
73.93/2000*(0.70410959)\
73.93/1,408.219180
=19,04800728
0.02%?
 
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It is useful to put brackets around denominators, otherwise expressions like a/b*c are interpreted as (a/b)*c instead of a/(b*c) as you used it here.

It looks fine up to the third line from the bottom. What does the 19,... do there? And where does the 0.02% come from?
0.02% of $2000 is less than a dollar. Clearly within less than a year you can’t get more than 70 dollars interest that way.
 
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