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Johnny deposited $50 in a savings bank at

the beginning of the year. Johnny’s money
earns him interest at the rate of 8 percent
of the amount deposited, for each year that
Johnny leaves his money in the bank. If
Johnny leaves his $50 in the bank for
exactly one year and then decided to
withdraw all of his money, how much
money (including interest) can he withdraw?
(The interest is not compounded.)

1 Answer

13 votes

Answer:

54 dollars

Step-by-step explanation:

Because this problem involves simple interest, and the money is only deposited for one year, you can calculate the amount of money in the bank after one year by thinking about a percent increase. Johnny starts with 50 dollars in his bank account, and we are given that he will experience an 8% increase over the year. This means that the amount of money in his bank account after one year is just 50 + 0.08*50 (the principal amount plus the simple interest, or amount of money that increases during the year). This is equal to 50 + 4, or 54 dollars.

Note that, whenever we are dealing with simple interest, the amount of money in the bank after a certain number of years is just P(1 + PRT), where P is the principal amount, R is the interest rate, and T is the number of years the money is in the bank.

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