Answers 247- THE FIVE CARDS
The number is either 3 9 1 5 7 or 5 7 1 3 9. In either case the product
of the two pairs 39 and 57, minus 1, results in 2222.
- SQUARES AND DIGITS
If a square number terminates in similar digits, those digits must be 4, as
in the case of 144, the square of 12. But there cannot be more than three equal
digits, and therefore the smallest answer is 1444, the square of 38.
- THE TWO ADDITIONS
Arrange the figures in the following way:173 85
4 92
177 177and both sums add up alike.
- THE REPEATED QUARTETTE
Multiply 273863 by 365 and the product is 99959995. Working the problem
backwards, any number whatever consisting of eight figures with the first four
repeated is divisible by 73 (and by 137) without remainder, and if it ends in
5 or 0 is divisible by 365 (or by 50005). Knowing this, the highest possible
product can be written down at once.
- EASY DIVISION
All we need do is to proceed as follows:7--7101449275362318840579
1014492753623188405797Divide 7 by 7, carry the I to the top line, divide again by 7 and carry the 0 to