PHP Numbers MCQ Questions and Answers

1. What is the largest integer value supported in 64-bit PHP?

a) 2^31 - 1

b) 2^63 - 1

c) 9,223,372,036,854,775,807

d) 4,294,967,295

Answer:

b) 2^63 - 1

Explanation:

In a 64-bit version of PHP, the largest integer is 2^63 - 1.

2. How is a hexadecimal number specified in PHP?

a) 0x followed by the number

b) # followed by the number

c) 0h followed by the number

d) Hex followed by the number

Answer:

a) 0x followed by the number

Explanation:

Hexadecimal numbers are specified with a leading 0x in PHP.

3. What function checks if a variable is a number or a numeric string in PHP?

a) is_num()

b) is_numeric()

c) is_number()

d) is_integer()

Answer:

b) is_numeric()

Explanation:

The is_numeric() function checks if a variable is a number or a numeric string.

4. How do you convert a string to an integer in PHP?

a) intval()

b) (int)

c) parse_int()

d) Both a) and b)

Answer:

d) Both a) and b)

Explanation:

intval() and casting with (int) are both used to convert a string to an integer.

5. What is the result of the expression 0.1 + 0.2 in PHP?

a) 0.3

b) 0.30000000000000004

c) 0.2

d) 0.4

Answer:

b) 0.30000000000000004

Explanation:

Due to floating-point precision, the sum of 0.1 and 0.2 may not exactly equal 0.3.

6. Which function can be used to format a number with grouped thousands in PHP?

a) number_format()

b) format_number()

c) group_number()

d) thousand_format()

Answer:

a) number_format()

Explanation:

The number_format() function is used to format numbers with grouped thousands.

7. What is the output of the following PHP code? echo (int)(8.9);

a) 8

b) 9

c) 8.9

d) Error

Answer:

a) 8

Explanation:

Casting a float to an int in PHP truncates the decimal part.

8. How do you define a float number in scientific notation in PHP?

a) 1.2E4

b) 1.2e4

c) Both a) and b)

d) 1.2 * 10^4

Answer:

c) Both a) and b)

Explanation:

Scientific notation in PHP can be written using either uppercase E or lowercase e.

9. What is the purpose of the PHP function round()?

a) To round a number to its nearest integer

b) To round a number to a specified number of decimal points

c) Both a) and b)

d) To eliminate the decimal part of a number

Answer:

c) Both a) and b)

Explanation:

round() can round a number to its nearest integer or to a specified number of decimal points.

10. How does PHP handle arithmetic operations on an integer that exceed its maximum value?

a) It causes an overflow error

b) It wraps around to the minimum value

c) It converts the number to a float

d) It returns NULL

Answer:

c) It converts the number to a float

Explanation:

PHP automatically converts integers to floats when they exceed their maximum value.

11. What is the output of the PHP expression var_dump(0123)?

a) int(123)

b) int(83)

c) string(4) "0123"

d) NULL

Answer:

b) int(83)

Explanation:

Numbers starting with 0 are interpreted as octal numbers. 0123 in octal is equivalent to 83 in decimal.

12. Which function checks whether a variable is a float in PHP?

a) is_float()

b) is_double()

c) is_real()

d) All of the above

Answer:

d) All of the above

Explanation:

is_float(), is_double(), and is_real() are all equivalent and check if a variable is of type float.

13. What is the maximum number of decimal digits guaranteed to be preserved in float operations in PHP?

a) 13

b) 14

c) 15

d) 16

Answer:

b) 14

Explanation:

PHP guarantees that at least 14 decimal digits can be preserved in float operations.

14. What is the result of the following PHP code? echo gettype(10.0);

a) integer

b) double

c) float

d) number

Answer:

b) double

Explanation:

In PHP, floating-point numbers are of the type double.

15. Which PHP function will return a string representation of a number in binary format?

a) decbin()

b) bindec()

c) hexbin()

d) bin2hex()

Answer:

a) decbin()

Explanation:

The decbin() function converts a decimal number to a binary string.