A group of 630 children is arranged in rows for a group photograph. Each row contains
three fewer children than the row in front of it. What number of rows is not possible?
Binary multiplication is done similarly to decimal multiplication, where each bit is multiplied individually. Let's break down \( 00_2 \times 11_2 \) step by step.
✅ Step 1: Understanding Binary Multiplication
We multiply each digit in the first binary number by each digit in the second binary number. The multiplication follows the same rules as decimal multiplication but with only 0's and 1's.
✅ Step 2: Perform the Multiplication
Let's multiply the two binary numbers:
First step: \( 0 \times 1 = 0 \)
Second step: \( 0 \times 1 = 0 \)
Third step: \( 0 \times 1 = 0 \)
✅ Step 3: Adding the Results
Since all the results are 0, the final multiplication result is also 0.
In 8-bit two's complement arithmetic, compute the result of the following addition:
A = 10011001, B = 11010111. What is the resulting 8-bit binary value?
Option (1) – True: Unicode was designed to be backward compatible with ASCII. The first 128 Unicode characters (U+0000 to U+007F) are identical to ASCII, ensuring compatibility.
Option (2) – False: ASCII uses 7 bits per character, while Unicode uses up to 16 bits or more (e.g., UTF-16, UTF-32 encodings).
Option (3) – False: Unicode and ASCII share the same first 128 characters; they are not completely different.
Option (4) – False: Unicode can represent far more characters than ASCII, not fewer.
✅ Correct Answer: (1) Unicode is backward compatible with ASCII and includes all ASCII characters in its encoding.
Each digit 6 → 9, increase = 3.
Count how many times digit 6 appears from 1 to 100.
Two-digit numbers (10–99):
Tens place = 6 → numbers 60–69 → 10 times
Units place = 6 → appears once in each decade (16, 26, ..., 96) → 9 times
Total digit 6 occurrences = $10 + 9 = 19$
Additionally, number 6 itself contributes 1 more occurrence.
So total 6s = $19 + 1 = 20$
Increase in sum = $20 \times 3 = 60$
But this does not match options → Check again carefully.
Correct counting:
Tens place occurrences:
60–69 → 10
Units place occurrences:
6, 16, 26, 36, 46, 56, 66, 76, 86, 96 → 10
Total = 20 occurrences.
Increase = $20 \times 3 = 60$
But total sum change involves positional value:
A “6” in tens place increases number by 30
A “6” in ones place increases by 3
Count tens-place 6s = 10 → total = $10 \times 30 = 300$
Count ones-place 6s = 10 → total = $10 \times 3 = 30$
Total change = $300 + 30 = 330$
A teacher gave a student the task of adding ‘N’ natural numbers starting from 1. After a while, the student reported his result as 700. The teacher replied that the result was wrong. The student realized he had added one number twice. Find the sum of digits of the number which the student had added twice.
When you reverse the digits of the number 13, the number increases by 18. How many other two digit numbers increase by 18 when their digits are reversed?
Let the two-digit number be $10a + b$.
Reversed number $= 10b + a$.
Given increase is $18$:
$(10b + a) - (10a + b) = 18$
$9(b - a) = 18$
$b - a = 2$
Possible digit pairs $(a,b)$ are:
$(1,3), (2,4), (3,5), (4,6), (5,7), (6,8), (7,9)$
Total such numbers $= 7$.
Consider
an arbitrary number system with independent digits as 0,1 and A. If we generate
first few numbers in sequence as 00, 01, 0A, 10, 11, 1A and if this process is
continued to generate the numbers, then the position of 10A is ________
A family has several children. Each boy in this family has as many sisters as brothers, but each girl has twice as many brothers as sisters. How many brothers and sisters are there?
A Group of 630 children are seated in n rows for a group photo session. Each row contains three less children than the row in front of it. Which one of the following number of rows is not possible?
405 sweets were distributed equally among a group of children such that the number of sweets received by each child is one-fifth of the number of children. The number of children in the group is
A bus starts from its depot filled to seating capacity. It stops at a point A where 1/6th of the passengers alight and 10 board the bus. At point B, 1/5th of the passengers alight and 3 board the bus. At point C which is the last stop, all the 55 passengers alight. The capacity of the bus is
Suppose the largest n bit number requires ‘d’ digits in decimal representation. Which of the following relations between ‘n’ and ‘d’ is approximately correct
Three players – Aalu, Kachaalu and Bhalu were playing poker.
At least one cheated.
Exactly one always spoke the truth, one always lied, and one alternated between truth and lie.
Which of the following can never be true?
Convert $(12x)_3$ to decimal:
$1\cdot 3^2 + 2\cdot 3 + x = 9 + 6 + x = 15 + x$
Convert $(123)_x$ to decimal:
$1\cdot x^2 + 2\cdot x + 3$
Equate:
$15 + x = x^2 + 2x + 3$
Bring all to one side:
$x^2 + x - 12 = 0$
Factor:
$(x + 4)(x - 3) = 0$
So $x = 3$ or $x = -4$
But base $x$ must be > 3 (because digits 1,2,3 appear).
Allowed value = 3 (but digit '3' cannot appear in base 3).
So no valid base exists.
A two digit number is such that the product of its digits is 12. If 36 is added to the number, the digits
interchange their places. What is the number?
Consider a sequence formed by concatenating the positive integers in increasing order:
12345678910111213 ... Which among the following is the closest to the 2028th digit in
this infinite sequence?