What is the minimum possible value of the 2-digit integer EF in the following CRYPTOGRAM? Where A, B, C, D, E and F are all distinct digits and 0 is not allowed to be a leading (first) digit..
A B + C D --- E F ---
33
A and C must be lowest digits- 1&2, and one of B or D can be 0, and the other will be next one greater than 2- so 3. We have 13+20=33 - the lowest number for EF.
For some positive integer k both 4^k and 5^k start with the same digit x in base 10 i.e. 4^k = x..... 5^k = x..... What is the sum of all possible values of x.
I'm thinking of a number.
What is the number?
i) It is a square number ii) It is an ordered number iii) Each digit of the number is a square number
A number is an ordered number when its digits are in an increasing sequence. For example, 136 is an ordered number but 163 is not.
