Volume 36
, Issue 2


In the previous issue of Parabola I discussed the derivation of the normal distribution of measurement errors by the famous German  mathematician Carl Friedrich Gauss in 1809. Gauss and the Normal Curve were featured on the front side a German banknote several years ago.

When people buy a home they usually have to borrow an appreciable fraction of its value from a bank or other financial institution.

Htsi si na raitlcf ero aparobal no oht wb oerka oceds.

I am sure that, like me, your immediate reaction to the above sentence was to try to “decipher” the message

Problem 1. You have a huge pile of 1¢, 2¢, 5¢, 10¢, 20¢, 50¢ and \$1 coins. Some number of coins, $N$ say, total $X$ ¢ . Show that you can make up $\$N$ using $X$ coins.

Q1072. Is it possible to fill the empty circles in the diagram below with the integers $0, 1, \ldots , 9$ so that the sum of the numbers at the vertices of each shaded triangle is the same?

Q1064. The numbers $1, 2, \ldots , 16$ are placed in the cells of a $4 \times 4$ table as shown in the left hand diagram below.