Show that `(111...1)/(91 "digits")` is a composite number.

How will you show that (17xx11xx2)+(17xx11xx5) is a composite number? Explain.

A number is selected at random from the first 25 natural numbers. If it is a composite number, then it is divided by 6. But if it is not a composite number, it is divided by 2. Find the probability that there will be no remainder in the division.

The sum of the digits of number consisting of the digits is 8. If 18 is deducted from the number. The digits of the number interchange the places. Find the number

The x=1111....1 of 91 times of is a (a) Even number. (b) Prime number. (c) Not a prime. (d) none of these

The unit digit of a two digit number exceeds its tens' digit by 7 and the product of two digits is less by 10 from the number. Find the quadratic equation.

find the number of positive number with three digits divisible dy 5 such that the digits in each number in each number are different

If the digits of a two digits' number are interchanged, then the number thus obtained is (5)/(6) part of the original number and the difference of the digits is 1. Find the number.

Number of six-digit numbers such that any digit that appears in the number appears at least twice, where the digits of each number are from the set {1, 2, 3, 4, 5}, is (Example 225252 is valid but 222133 is not valid)

The sum of the two digits of a two digits' number is 9. if the digits are interchanged, then the number thus obtained is 27 more than the original number. Find the number.

The number 916238457 is an example of a nine-digit number which contains each of the digit 1 to 9 exactly once. It also has the property that the digits 1 to 5 occur in their natural order, while the digits 1 to 6 do not. Find the number of such numbers.