C Programming MCQs with answers Page - 2

Floating-Point Precision:

• In C, the float data type typically provides only 6–7 decimal places of precision.
• The given number 15.621212121212 has more than 7 decimal places.
• Since fl is declared as a float, the extra decimal places get truncated.

printf("%f", fl); Behavior:

• By default, %f prints floating-point numbers with 6 decimal places.
• So, the output will be 15.621212 (truncated after 6 places).

Correct Answer:

✅ (D) 15.621212

Bonus Notes:

• If you want more decimal places, use double instead of float:
• To control the decimal places in printf, use:This will print 12 decimal places (if precision allows).

printf("%.12f", fl);

double fl = 15.621212121212;

printf("%lf", fl);

%.0f Format Specifier:

• In printf("%.0f", 4.89);, the .0 means the number will be rounded to zero decimal places (i.e., an integer value).
• The %.0f format rounds the floating-point number to the nearest integer using standard rounding rules.

Rounding Behavior:

• 4.89 is closer to 5 than to 4.
• Since printf("%.0f", 4.89); rounds normally, 4.89 rounds up to 5.

Correct Answer:

✅ (D) 5

Bonus Notes:

• If you use printf("%.2f", 4.89);, the output will be: 4.89
• If you use printf("%.1f", 4.89);, the output will be: 4.9
• %.0f will always round to the nearest whole number.

• int, float, and long are numeric data types used for storing numbers.
• char, on the other hand, is a character data type, used for storing a single character.

Since char is not a numeric type, it is the odd one out.

Correct Answer:

✅ (C) char

• %f is a format specifier in C language used for printing floating-point numbers (i.e., float and double types).
• It is used with printf() and scanf() functions to handle floating-point values.

Example:

#include <stdio.h>

int main() {

    float num = 12.345;

    printf("The number is: %f

", num);

    return 0;

}

Output:

The number is: 12.345000

Breakdown of Options:

Correct Answer:

✅ (B) Floating type

In a 32-bit compiler, the size of a float data type is 4 bytes (32 bits) because:

• A float in C follows the IEEE 754 single-precision floating-point standard, which uses:
  • 1 bit for the sign
  • 8 bits for the exponent
  • 23 bits for the mantissa (fraction)

Verification with C Code:

You can check the size of float using:

#include <stdio.h>

int main() {

    printf("Size of float: %zu bytes

", sizeof(float));

    return 0;

}

Output:

Size of float: 4 bytes

Final Answer:

✅ (B) 4

In a 32-bit compiler, the typical sizes of fundamental data types are:

• int and float both take 4 bytes in a 32-bit compiler.
• double is 8 bytes, so option (A) is incorrect.
• short is 2 bytes while int is 4 bytes, so (B) is incorrect.
• char is 1 byte, while short is 2 bytes, so (C) is incorrect.

Final Answer:

✅ (D) int and float