ABACUS - JANUARY 2012 : LEVEL 7 - 8


PROBLEM 1. The ages of a father and his two different-aged sons are the powers of the same prime number. Last year everybody's age was a prime number. How old are they now?

PROBLEM 2. Could the sum of seven consecutive integers be a prime number?

PROBLEM 3. A 5-digit number is divisible by 7, 8, and 9. The number created from the first two digits is a prime number, 1 greater than a square number, and the sum of these two digits is a two-digit number. Find this 5-digit number.

PROBLEM 4. Every digit of a 5-digit number is either 1 or a prime number. Not only that, but any number created by any 2, 3, or 4 consecutive digits of this number are prime numbers also. Find this number, and check if it is a prime number or not.

PROBLEM 5. Can you put the numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 into two groups so that the sums of the numbers in each group is the same? Can you do this to get the same product in each group?

PROBLEM 6. Are there any five consecutive whole numbers, which can be put into two groups so that the product of the numbers in each group is the same?

PROBLEM 7. In some cases, when 22022 and 20222 are divided by the same 3-digit number, they give the same remainder. Which one of these divisors can be determined by the remainder?

PROBLEM 8. Find a, b, c, and d, such that abb = bccbdc

0 Response to "ABACUS - JANUARY 2012 : LEVEL 7 - 8"

Post a Comment

powered by Blogger | WordPress by Newwpthemes | Converted by BloggerTheme