HTML and CSS Reference
In-Depth Information
Exercises
1. Create an array of five animals. Use a
for
loop to display the values stored there.
Now add two more animals to the end of the array and sort the array. (Use Java-
Script's built-in array methods.) Display the sorted array.
2. Create an associative array called
colors
. Each element of the array is a string
representing the color, for example,
red
or
blue
. Use the
for/in
loop to view each
element of the array with a color of the font the same color as the value of the
array element being displayed.
3. Create a function that will return the current month by its full name. Use the
Date
object to get the current month. Months are returned as 0 for January, 1 for
February, 2 for March, and so on. Output should resemble this:
The current month is January.
Hint: You can create an array, starting at index 0, and assign a month value to it;
for example,
month[0]=“January”
or use a
switch
statement, for example,
case 0:
return “January”
.
4. An invoice is due and payable in 90 days. Write a function that will display that
date.
5. How many days until your birthday? Write a function to calculate it.
6. To calculate the balance on a loan, the following formula is used:
PV
=
PMT
* ( 1 - (1 +
IR
)
-NP
) /
IR
PV
is the present value of the loan;
PMT
is the regular monthly payment of the
loan;
IR
is the loan's interest rate;
NP
is the number of payments remaining.
Write a JavaScript statement to represent this formula.
7. Using the formula to calculate the loan balance from the last exercise, write a
function that will calculate the principal balance left on a loan where the monthly
payments are $600, the annual interest rate is 5.5 percent, and there are 9 years
remaining on the loan. Use the
toFixed() Number
method to format the output.
8. Apply the
ceil()
,
floor()
, and
round()
methods to the number 125.5567 and dis-
play the results.
9. Create an array of 10 fortune cookies that will be randomly displayed each time
the user reloads the page. The fortune will be a saying like: “Procrastination is
the thief of time.”
