Lolla bought a balloon at the circus. She gave the clown six
coins to pay for it. What could Lolla have paid for the balloon?
There are 78 prisoners in a square cell block of twelve cells.
The clever prison warder arranged them so there were 25 along
each wall of the prison block. How did he do it? Put operations
signs between the numbers 3 4 5 6 to make the highest possible
number and lowest possible number. Use 4 four times with simple
operations so that you get the answer 12. Can you make 15, 16
and 17 too? Can you make square numbers by adding two prime
numbers together? Ten cards are put into five envelopes so that
there are two cards in each envelope. The sum of the numbers
inside it is written on each envelope. What numbers could be
inside the envelopes? A magician took a suit of thirteen cards
and held them in his hand face down. Every card he revealed had
the same value as the one he had just finished spelling. How did
this work? Four bags contain a large number of 1s, 3s, 5s and
7s. Pick any ten num