Recent questions tagged number-systems

1 vote
1
How many pair of natural numbers are there, the differences of whose squares is $45$ ? $1$ $2$ $3$ $4$
2
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 : $45$ $36$ $54$ $63$
1 vote
3
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 : $18$ $24$ $81$ $42$
Find the number of numbers between $300$ to $400$ (both included) that are not divisible by $2,3,4$ and $5$ $50$ $33$ $26$ $17$
$x$ is a whole number. If the only common factors of $x$ and $x2$ are $1$ and $x,$ then $x$ is ________. $1$ a perfect square an odd number a prime number
The value of $[(10)^{150}\div (10)^{146}]$: $1000$ $10000$ $100000$ $10^{6}$