Recent questions tagged number-systems

2 2 votes
1 1 answer
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Let $n$ and $m$ be two positive integers such that there are exactly $41$ integers greater than $8^{m}$ and less than $8^{n}$, which can be expressed as powers of $2$. Th...
4 4 votes
1 1 answer
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The sum of the first two natural numbers, each having 15 factors (including 1 and the number itself), is
1 1 vote
1 1 answer
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If $x$ is a positive real number such that $x^{8}+\left(\frac{1}{x}\right)^{8}=47$, then the value of $x^{9}+\left(\frac{1}{x}\right)^{9}$ is$34 \sqrt{5}$$40 \sqrt{5}$$36...
1 1 vote
1 1 answer
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Let $n$ and $m$ be two positive integers such that there are exactly $41$ integers greater than $8^{m}$ and less than $8^{n}$, which can be expressed as powers of $2$. Th...
0 0 votes
0 0 answers
931
931 views
The sum of the first two natural numbers, each having $15$ factors (including $1$ and the number itself), is
2 2 votes
1 1 answer
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For any natural numbers $\mathrm{m}, \mathrm{n}$, and $\mathrm{k}$, such that $\mathrm{k}$ divides both $m+2 n$ and $3 m+4 n \mathrm{k}$ must be a common divisor of$m$ an...
1 1 vote
0 0 answers
903
903 views
Let $\mathrm{a}, \mathrm{b}, \mathrm{m}$ and $\mathrm{n}$ be natural numbers such that $a>1$ and $b>1$. If $a^{m} b^{n}=144^{145}$, then the largest possible value of $n-...
1 1 vote
0 0 answers
909
909 views
The number of positive integers less than $50$, having exactly two distinct factors other than $1$ and itself, is
1 1 vote
0 0 answers
788
788 views
The price of a precious stone is directly proportional to the square of its weight. Sita has a precious stone weighing $18$ units. If she breaks it into four pieces with ...
1 1 vote
0 0 answers
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Let both the series $a_{1}, a_{2}, a_{3}, \ldots$ and $b_{1}, b_{2}, b_{3} \ldots$ be in arithmetic progression such that the common differences of both the series are pr...
1 1 vote
0 0 answers
963
963 views
Let $n$ be the least positive integer such that $168$ is a factor of $1134^{n}$. If $m$ is the least positive integer such that $1134^{n}$ is a factor of $168^{m}$, then ...
1 1 vote
0 0 answers
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The number of integer solutions of equation $2|x|\left(x^{2}+1\right)=5 x^{2}$ is
1 1 vote
1 answers 1 answer
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The number of all natural numbers up to $1000$ with non-repeating digits is$648$$585$$504$$738$
1 1 vote
1 1 answer
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A shop owner bought a total of $64$ shirts from a wholesale market that came in two sizes, small and large. The price of a small shirt was $\text{INR} \; 50$ less than th...
1 1 vote
1 1 answer
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If $n$ is a positive integer such that $( \sqrt[7]{10}) ( \sqrt[7]{10})^{2} \dots ( \sqrt[7]{10})^{n} 999,$ then the smallest value of $n$ is
1 1 vote
1 1 answer
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For a $4$-digit number, the sum of its digits in the thousands, hundreds and tens places is $14,$ the sum of its digits in the hundreds, tens and units places is $15,$ an...
1 1 vote
1 1 answer
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How many three-digit numbers are greater than $100$ and increase by $198$ when the three digits are arranged in the reverse order?
2 2 votes
2 answers 2 answers
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The natural numbers are divided into groups as $(1), (2,3,4), (5,6,7,8,9), \dots $ and so on. Then, the sum of the numbers in the $15 \text{th}$ group is equal to $6090$$...
0 0 votes
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How many integers in the set $\{ 100, 101, 102, \dots, 999\}$ have at least one digit repeated $?$
0 0 votes
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Let $\text{N}, x$ and $y$ be positive integers such that $N = x + y, 2 < x < 10$ and $14 < y < 23.$ If $\text{N} 25,$ then how many distinct values are possible for $\...
2 2 votes
1 1 answer
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How many of the integers $1,2, \dots, 120,$ are divisible by none of $2,5$ and $7 ?$$40$$42$$43$$41$
2 2 votes
1 1 answer
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If $\textsf{x}$ and $\textsf{y}$ are non-negative integers such that $\textsf{x+9=z, y+1=z}$ and $\textsf{x+y<z+5},$ then the maximum possible value of $\textsf{2x+y}$ eq...
1 1 vote
1 1 answer
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Among $100$ students, $x_{1}$ have birthdays in January, $x_{2}$ have birthdays in February, and so on. If $x_{0}= \text{max}\left ( x_{1},x_{2},\dots,x_{12} \right ),$ t...
3 3 votes
2 answers 2 answers
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How many pair of natural numbers are there, the differences of whose squares is $45$ ? $1$$2$$3$$4$
1 1 vote
1 answers 1 answer
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A certain number consists of two digits whose sum is $9$. It the order of digits is reversed, the new number is $9$ less than the original number. The original number is ...
3 3 votes
1 answers 1 answer
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A two digit number is such that the product of the digits is $8$. When $18$ is added to the number, the digits are reversed. The number is :$18$$24$$81$$42$
0 0 votes
1 answers 1 answer
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Find the number of numbers between $300$ to $400$ (both included) that are not divisible by $2,3,4$ and $5$$50$$33$$26$$17$
0 0 votes
1 1 answer
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By which one of the following should we multiply $152207$ so that the product is $11111111$?$53$$63$$73$$83$
1 1 vote
1 1 answer
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$x$ is a whole number. If the only common factors of $x$ and $x2$ are $1$ and $x,$ then $x$ is ________.$1$a perfect squarean odd numbera prime number
1 1 vote
1 1 answer
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The value of $[(10)^{150}\div (10)^{146}]$:$1000$$10000$$100000$$10^{6}$
1 1 vote
1 1 answer
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How many pairs $(m,n)$ of positive integers satisfy the equation $m^{2}+105=n^{2}$ _______
1 1 vote
1 1 answer
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In a six-digit number, the sixth, that is, the rightmost, digit is the sum of the first three digits, the fifth digit is the sum of first two digits, the third digit is e...
5 5 votes
1 answers 1 answer
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How many factors $2^{4}\times3^{5}\times10^{4}$ are perfect squares which are greater than $1$ _______
2 2 votes
1 1 answer
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The smallest integer $n$ such that $n^{3} - 11n^{2} + 32n - 28 >0$ is
3 3 votes
1 1 answer
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How many two-digit numbers, with a non-zero digit in the units place, are there which are more than thrice the number formed by interchanging the positions of its digits?...
2 2 votes
1 1 answer
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Let $t_{1}, t_{2},\dots$ be a real numbers such that $t_{1}+t_{2}+\dots+t_{n}=2n^{2}+9n+13$, for every positive integers $n\geq2$.If $t_{k}=103$ , then $k$ equals
2 2 votes
1 1 answer
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If $\text{N}$ and $x$ are positive integers such that $\text{N}^{\text{N}}=2^{160}$ and $\text{N}^{2} + 2^{\text{N}}$ is an integral multiple of $2^{x}$, then the largest...
3 3 votes
2 2 answers
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If the sum of squares of two numbers is $97$, then which one of the following cannot be their product?$-32$$48$$64$$16$
1 1 vote
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If $\text{A}=\left \{6^{2n} – 35n – 1: n=1,2,3 \dots \right \}$ and $\text{B}= \left \{35\left (n – 1 \right ) : n=1,2,3\dots \right \}$ then which of the following is t...
2 2 votes
1 1 answer
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The smallest integer $n$ for which $4^{n}>17^{19}$ holds, is closest to$33$$37$$39$$35$