Why loops are needed in Javascript - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to print numbers from 1 to 3 using a loop.

Javascript

for(let i = 1; i [1] 4; i++) {
  console.log(i);
}

Drag options to blanks, or click blank then click option'

A>

B<

C<=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' will never run the loop.

Using '==' will only run when i equals 4.

The loop should run while i is less than 4 to print numbers 1, 2, and 3.

2fill in blank

medium

Complete the code to sum numbers from 1 to 5 using a loop.

Javascript

let sum = 0;
for(let num = 1; num [1] 6; num++) {
  sum += num;
}
console.log(sum);

Drag options to blanks, or click blank then click option'

A<=

B<

C>

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' will exclude 5, which is needed.

Using '>' will not run the loop.

The loop should run while num is less than or equal to 5 to include numbers 1 through 5.

3fill in blank

hard

Fix the error in the loop condition to print 'Hello' 3 times.

Javascript

for(let count = 0; count [1] 3; count++) {
  console.log('Hello');
}

Drag options to blanks, or click blank then click option'

A<

B>=

C==

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>=' will cause the loop to never run.

Using '==' will only run once.

The loop should run while count is less than 3 to print 'Hello' three times.

4fill in blank

hard

Fill both blanks to create a loop that prints even numbers from 2 to 10.

Javascript

for(let i = [1]; i [2] 11; i += 2) {
  console.log(i);
}

Drag options to blanks, or click blank then click option'

A2

B<

C<=

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Starting from 1 will print odd numbers.

Using '<=' will include 12 which is not needed.

Start from 2 and loop while i is less than 11 to print even numbers up to 10.

5fill in blank

hard

Fill all three blanks to create a loop that prints numbers from 5 down to 1.

Javascript

for(let num = [1]; num [2] 0; num [3]) {
  console.log(num);
}

Drag options to blanks, or click blank then click option'

A5

B>

C--

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' will cause the loop to never run.

Using '++' will increase instead of decrease.

Start from 5, loop while num is greater than 0, and decrease num by 1 each time.