Sharp EL-W531X

If the principal is a (¥), the annual interest rate is r (%),
and the number of years of interest accumulation is x (years),
the final amount y (¥) is given by the following equation:
(1) Find the final amount when a principal of ¥400,000 is
deposited for three years at an annual interest rate of 5%
and the interest is compounded annually.
(2) When a principal of ¥300,000 is deposited f
or five years
and the interest is compounded annually, the final amount is
¥339,422. The annual interest rate r is given by the equation below.
Find the annual interest rate r.
(1)
(2)
x
r = 100 - 1( )
y
a
5
- 1
339422
300000
y = 400000 1 +
( )
5
100
3
r = 100
( )
5
100
300000
y = a ( 1 + r / 100 )
x
400000
1
3
100
5 339422
1
Operation Display
<Example 2>
Power and Radical root
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