Abstract methods in Typescript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare an abstract method named display.

Typescript

abstract class Vehicle {
  abstract [1](): void;
}

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Aprint

Bshow

Cdisplay

Drun

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different method name than display.

Trying to provide a method body in the abstract method.

The abstract method must be declared with the exact name display as required.

2fill in blank

medium

Complete the code to make Vehicle an abstract class.

Typescript

abstract class [1] {
  abstract display(): void;
}

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AVehicle

BCar

CTransport

DMachine

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different class name than Vehicle.

Not declaring the class as abstract (though not asked here).

The class must be named Vehicle to match the abstract method declaration context.

3fill in blank

hard

Fix the error in the subclass by correctly implementing the abstract method display.

Typescript

abstract class Vehicle {
  abstract display(): void;
}

class Car extends Vehicle {
  [1] display(): void {
    console.log('Car display');
  }
}

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Aoverride

Babstract

Cprivate

Dpublic

Attempts:

3 left

💡 Hint

Common Mistakes

Using abstract keyword in subclass method implementation.

Using private which restricts access and causes errors.

The method must be declared public to correctly implement the abstract method from the base class.

4fill in blank

hard

Fill both blanks to declare an abstract method calculateSpeed that returns a number.

Typescript

abstract class Vehicle {
  abstract [1](): [2];
}

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AcalculateSpeed

Bstring

Cnumber

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong return type like string or void.

Using a different method name.

The method name is calculateSpeed and it returns a number type.

5fill in blank

hard

Fill all three blanks to implement the abstract method calculateSpeed in subclass Bike that returns a number.

Typescript

abstract class Vehicle {
  abstract calculateSpeed(): number;
}

class Bike extends Vehicle {
  [1] [2](): [3] {
    return 50;
  }
}

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

Apublic

BcalculateSpeed

Cnumber

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Using void as return type instead of number.

Using wrong method name or missing access modifier.

The method must be declared public, named calculateSpeed, and return type number.