Q
What will be the value of x after the following code: let x = 10; x += 5;

Answer & Solution

Answer: Option C
Solution:
x += 5 is equivalent to x = x + 5, so x becomes 15.
Related Questions on Average

Can a constant objects properties be changed?

A). Yes

B). No

C). Only if redeclared

D). Only with special methods

What will be the output of let { a, b } = { a: 1, b: 2, c: 3 };?

A). a is 1, b is 2

B). a is 2, b is 3

C). a is 1, b is undefined

D). a is 3, b is undefined

What will const x = { a: 1 }; x.a = 2; do?

A). Throw an error

B). Change x.a to 2

C). Change x to 2

D). Do nothing

What is the result of let x = 10; x -= 3;?

A). 7

B). 13

C). 10

D). 3

What is the outcome of let x = 8; x %= 3;?

A). 1

B). 2

C). 3

D). 5

What will be the result of let { a, b } = { a: 3, b: 4 };?

A). a is 4, b is 3

B). a is 3, b is 4

C). a is undefined, b is undefined

D). a is null, b is null

What does let { a: alpha, b: beta } = { a: 1, b: 2 }; do?

A). Creates variables alpha and beta with values 1 and 2

B). Creates variables a and b with values 1 and 2

C). Throws an error

D). Assigns default values

Which assignment will fail?

A). const x = 10; x = 20;

B). let y = 5; y = 10;

C). var z = 15; z = 30;

D). let a = { b: 2 }; a.b = 3;

What is the equivalent of x *= 4?

A). x = x + 4

B). x = x / 4

C). x = x * 4

D). x = 4

How can you swap the values of two variables a and b in one line?

A). [a, b] = [b, a]

B). a = b, b = a

C). a == b, b == a

D). a === b, b === a