Try to decipher this excerpt from the book “Alice Through the Looking Glass”:
“Zkhq L xvh d zrug,” Kxpswb Gxpswb vdlg, lq udwkhu d vfruqixo wrqh, “lw phdqv mxvw zkdw L fkrrvh lw wr phdq – qhlwkhu pruh qru ohvv”.
The text is encrypted using the Caesar Cipher technique where each letter is replaced with a different letter a fixed number of places down in the alphabet. Note that the capital letters have not been removed from the encryption.
Try to make a square from a set of rods:
6 rods of length 1 cm, 3 rods of length 2 cm each, 6 rods of length 3 cm and 5 rods of length 4 cm. You are not able to break the rods or place them on top of one another.
Find the largest six-digit number, for which each digit, starting with the third, is equal to the sum of the two previous digits.
Find the largest number of which each digit, starting with the third, is equal to the sum of the two previous digits.
Find the missing numbers:
a) 4, 7, 12, 21, 38 ...;
b) 2, 3, 5, 9, ..., 33;
c) 10, 8, 11, 9, 12, 10, 13, ...;
d) 1, 5, 6, 11, 28, ....
In the equation \(101 - 102 = 1\), move one digit in such a way that that it becomes true.
What are the eight coins you need to take, so that you can use them to pay without change any amount from 1 pence up to 1 pound?
(In circulation at the time, there were coins of 1, 3, 5, 10, 20 and 50 pence).
It is known that in January there are four Fridays and four Mondays. What day of the week is January 1st?
How, without any means of measurement, can you measure a length of 50 cm from a shoelace, whose length is \(2/3\) meters?
Find out the principles by which the numbers are depicted in the tables (shown in the figures below) and insert the missing number into the first table, and remove the extra number from the second table.