The monthly interest rate on Bill’s credit card is 2% (24% nominal annual rate convertible monthly). For each of 9 consecutive school months, he borrows 500 at the beginning of the month. At the end of each of these 9 months, he makes the minimum payment of 25. Then, during the 3 remaining months of the year, he pays back X at the end of each month and borrows nothing. At the end of the 12 months his balance is 0. Determine X.

1725

Step-by-step explanation:

Bill borrowing per month = 500

For 9month his borrowing =9×500

=4500

Interest paid per month = 2%

M1 2

M22+2

M32+2+2

M42+2+2+2

M99(2%)

Total amount(A) due on interest in 9month

A= 2+4+6+8+10+12+14+16+18 =90(2%)

= 90 × 0.02 × 500

A = 900

Total debt (D) at the end of 9month is given by:

D = 4500 +900

= 5400

Bill:s month payment= 25

Bill's payment in 9 months = 25 ×9

= 225

We set up an equation as follows;

225 + 3X = 5400

3X = 5175

X = 1725

Total debt in 9month = 4500 + 90

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: