To see the answer, pass your mouse over the colored area.
To cover the answer again, click "Refresh" ("Reload").
Do the problem yourself first!


12.  Write the three rules which relate the Amount, the Base, and the
12.  Percent.

Amount   Base × Percent
Base   Amount ÷ Percent
Percent   Amount ÷ Base

13.  To find the unknown number, multiply only to find the Amount.

  14.  With a calculator, how do we interpret the fraction  Amount

Amount ÷ Base

Apply the rules to the following banking problems.  To recognize which is the Amount and which is the Base, rephrase each problem in this form:

___ is ___% of ___ ?

Written calculations

15.  Harold deposited $1,250 in a bank where the rate of interest is 3%
15.  annually.  In one year, how much interest will he earn?  $37.50

16.  Irene wants to earn $300 in interest towards her vacation next year.
16.  The bank is paying 6% interest. How much should she deposit?


17.  Jane deposited $800 and got $32 in interest.  What was the rate of
17.  interest?  (Use the method of proportions.)  4%

18.  If the bank pays 5¼% interest, and you deposit $2500, how much
18.  money in interest will you earn?  $131.25

19.  Jason received an interest payment of $137.50 from a deposit of
19.  $2500.  What was the rate of interest?  5.5%

Calculator Problems

  20.  Theresa invested $725 in a CD at 5 3
%.  How much interest will she

20.  earn?  $41.69

  21.  If Theresa earned $725 in interest at 5 3
%, how much did she

20.  deposit?  $12,608.70

22.  Raymond deposited $1600 into a CD, for which he got $76.50 in
22.  interest.  What was the rate of interest?  4.8%

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