GK: Class 12 General Q&A · Page 25
3,658 free answers on GK (General) for Class 12 students, across CBSE, ICSE and State boards.
Question & Answer
Questions
- GeneralClass 12All
What does the ace ♠ mean
The ace of spades (♠) is the highest-ranking card in the spade suit in most standard card games, and it carries unique cultural significance beyond its gameplay value. In many card games, aces can serve as either the highest or lowest card depending on context, but the ace of spades specifically often receives special visual treatment—it's typically the most ornately designed card in the deck, sometimes featuring the manufacturer's logo or elaborate artwork. Historically,
- GeneralClass 12All
Why is 170 the highest factorial
170 factorial (170!) is commonly cited as the highest factorial exactly representable using standard double-precision floating-point format (the 64-bit float format used by most programming languages) because 171! exceeds approximately 1.798 × 10^308, which is the maximum value this format can represent—anything larger returns as "infinity" in computational systems. This limitation arises from how computers store floating-point numbers using the IEEE 754 standard, which al
- GeneralClass 12All
What is the digit sum of 6372819923
The digit sum of 6372819923 is calculated by adding all individual digits: 6 + 3 + 7 + 2 + 8 + 1 + 9 + 9 + 2 + 3 = 50. This can be further reduced to a single digit by repeating the process: 5 + 0 = 5, which is called the digital root of the number. Digit sums serve practical purposes in mathematics: they help check divisibility (a number is divisible by 3 if its digit sum is divisible by 3, and divisible by 9 if its digit sum is divisible by 9), so since 50 is not divisible by 3 or 9
- GeneralClass 12All
What is the rarest card deck
The rarest playing card decks are typically unique historical artifacts or extremely limited modern luxury editions. The most valuable individual cards include the 1909 T206 Honus Wagner baseball card (not a playing card but often conflated in discussions) and historical decks like the ancient Chinese money-suited cards from the Tang Dynasty or hand-painted European decks from the 15th century that survived in extremely limited numbers. Among collectable modern playing card decks, ext
- GeneralClass 12All
What's faster than factorial
Several functions grow faster than factorial, most notably the double factorial, superfactorial, and hyperfactorial functions, though these still pale in comparison to truly explosive growth rates like those in the Ackermann function, Graham's number construction, or TREE(3) sequences. In practical computational contexts, exponential functions grow slower than factorials—for instance, 2^n grows much slower than n!—but tetration (repeated exponentiation) and higher hyperoperations
- GeneralClass 12All
What is the biggest factorial number
There is no "biggest" factorial number in a mathematical sense—factorials extend infinitely since you can always compute (n+1)! for any given n. However, practical computational limits exist: 170! is often cited as the largest factorial exactly representable in standard double-precision floating-point format before the result exceeds representable values and returns infinity in most programming environments. Using arbitrary-precision arithmetic, mathematicians have computed fact
- GeneralClass 12All
What is the highest power of 12 in 54
The highest power of 12 in 54 factorial (54!) is 26—meaning 12^26 divides evenly into 54!, but 12^27 does not. To find this, you need to count the minimum of the powers of 12's prime factors (12 = 2² × 3) that appear in 54!: specifically, you need pairs of twos and one three for each factor of 12. The calculation requires counting powers of 2 and 3 in 54! separately using Legendre's formula. For twos: ⌊54/2⌋ + ⌊54/4⌋ + ⌊54/8⌋
- GeneralClass 12All
What is the trick for 999 in math
The most useful trick with 999 involves recognizing it equals 1000 - 1, which simplifies multiplication: to multiply any number by 999, multiply by 1000 and subtract the original number. For example, 47 × 999 = 47 × 1000 - 47 = 47,000 - 47 = 46,953. This method works because distributing the subtraction (n × 999 = n × (1000 - 1) = 1000n - n) transforms a potentially difficult multiplication into simple operations. Additional patterns with 999 include recognizin
- GeneralClass 12All
Why is 52 factorial so special
52 factorial (52!) is approximately 8.0658 × 10^67, and its special significance lies in representing the number of possible arrangements of a standard 52-card deck—meaning every time you shuffle a deck thoroughly, you're almost certainly creating an arrangement that has never existed before in human history and will likely never occur again. This astronomical number exceeds the total number of atoms on Earth by many orders of magnitude. The magnitude of 52! makes it a pow
- GeneralClass 12All
How many zeros are in 1 duotrigintillion
One duotrigintillion contains 99 zeros following the 1 in American numbering convention, representing 10^99. The name breaks down as: "duo" means two, "triginti" means thirty, so duotrigintillion represents the 32nd power of 1,000 beyond 1,000 itself (1,000^33), which equals 10^99 since each thousand-step multiplies the exponent by three. This number sits just below the famous googol (10^100), which is merely ten times larger—a comparison that illustrates how quickly these numbe
- GeneralClass 12All
What is bigger than a sextillion
Many numbers are larger than a sextillion (10^21), starting with septillion (10^24), which is 1,000 times larger, followed by octillion (10^27), nonillion (10^30), and continuing through the systematic naming pattern. The sequence extends indefinitely: decillion (10^33), vigintillion (10^63), centillion (10^303 in American convention), and beyond, with each step representing multiplication by 1,000. Beyond named numbers in the standard system, mathematicians work with special large nu
- GeneralClass 12All
What is 1 unvigintillion
One unvigintillion equals 1 followed by 66 zeros (1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000) in American numbering convention, representing 10^66. The name derives from Latin: "un" means one and "viginti" means twenty, so unvigintillion represents the 21st power of 1,000 beyond 1,000 itself (1,000^22). Numbers at the unvigintillion scale rarely appear in practical applications but do emerge in theoretical physics and cosmology. For refer
- GeneralClass 12All
What number is this 100000000000000000000
The number 100,000,000,000,000,000,000 (1 followed by 20 zeros) is called 100 quintillion, or equivalently, one hundred quintillion. In exponential notation, it's written as 10^20 or 1 × 10^20, placing it firmly in the range of very large but occasionally referenced quantities in scientific and statistical contexts. Numbers at the 10^20 scale appear in specific domains: there are approximately 10^21 stars in the observable universe (ten times this number), global internet traffi
- GeneralClass 12All
Does 1 zillion exist
"Zillion" is not a defined mathematical number—it's an informal, colloquial term used to express an indefinitely large but unspecified quantity, similar to "gazillion," "bajillion," or "umpteen." While it appears frequently in casual conversation to indicate "a very large amount," it has no precise value in mathematics and wouldn't appear in scientific, technical, or formal academic contexts. The informal nature of "zillion" serves a linguistic purpose: it allows people to convey the co
- GeneralClass 12All
Do feet change as you age
Yes, feet often widen and flatten with age. Ligaments lose elasticity, and arches can drop, which is why many adults need wider shoes over time.
- GeneralClass 12All
What is the average foot size for men
The global average is around US men’s size 9–10. This varies by region, height, and genetics, but most mass-market footwear is built around this range.
- GeneralClass 12All
Can I use my phone to measure my foot size
Yes, but accuracy varies. Camera distortion and scaling issues mean phone measurements should be used as estimates, not replacements for physical measurement.
- GeneralClass 12All
What makes a number composite?
A composite number is any positive integer greater than 1 that has more than two factors—meaning it can be divided evenly by at least one number other than 1 and itself. Unlike prime numbers, which have exactly two factors, composite numbers are built from smaller whole numbers multiplied together. For example, 12 is composite because it can be divided by 1, 2, 3, 4, 6, and 12, making it the product of multiple factor pairs like 2 × 6 or 3 × 4. Understanding what mak
- GeneralClass 12All
Is 1 a composite number?
No, 1 is not classified as a composite number, nor is it considered a prime number—it occupies a unique position as a "unit" in number theory. By definition, a composite number must have more than two distinct positive divisors, while 1 has only one divisor: itself. This exclusion is not arbitrary but rather a deliberate mathematical convention that preserves the fundamental theorem of arithmetic, which states that every integer greater than 1 has a unique prime factorization. I
- GeneralClass 12All
What are composite numbers from 1 to 100?
Composite numbers from 1 to 100 include all positive integers in that range that have more than two factors, specifically: 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, and 100. That's 74 composite numbers in this range, compared to just 25 prime numbers, dem