I am a three digit number, and the following things are true about me:

1. The product of two of my digits is 8.
2. The sum of my digits is 13.
3. My first digit is four times my second digit.

What number am I?

When Shrek asks Fiona for her telephone number, Fiona is a bit coy about it, and tells Shrek the following information:

• My telephone number has 10 digits.
• There are no repeated digits in my telephone number.
• The first three digits are in ascending order.
• The second three digits are in descending order.
• Both the last four digits and the last two digits are multiples of sixty.
• My last four digits are not a multiple of 43.
• My first three digits are the square of an integer less than twenty.
• The sum of the second three digits is 14.

What number should Shrek dial?

My digits are all odd, and they add to 18. My first digit is four more than my last digit, the product of my digits is between 300 and 315, and I am less than 100,000. If my digits are not in descending order, what numbers could I be?

Two positive integers, A and B, both have 3 digits. A is bigger than B. A – B is between 300 and 400. What is the value of A - B?

 

In the addition problem below, some digits are missing. They have been replaced by x and y. Find the values of x and y.

3xy2 + 3y1 = 40x3

All my digits are non-zero perfect squares. If you treat my first two digits as a two-digit number, and treat my last two digits as a two-digit number, the sum of these two numbers is also a perfect square. If I am a three digit number, what numbers could I be?