Humanising Language Teaching
Year 6; Issue 1; January 2004

2 New Puzzles ( with solutions)

by Marie Agrell , France
marieagrell@teacher.com

A whale, elephants, and baby hippopotami

To balance a seesaw, put five elephants and a baby hippopotamus on one end, and a whale on the other. If you are the skinny type (50 kg), you can also climb on an elephant and stand on one end with twelve baby hippopotami on the other. And if you're on the heavy side (200 kg) stand on one of the ends with eleven baby hippopotami and put an elephant on the other. How many tons does the whale weigh?

A Russian campaign

On June 25, 1812, Napoleon's army entered Russia. Almost immediately, 22% of the army deserted. Then came a terrible epidemic that killed 8 % of the remaining soldiers, followed by the battle of Borodino where 6% of the remaining army was destroyed. When the army reached Moscow, a fire burned 5% of the remaining solders. While fleeing to France, another 4% of the combatants were lost in the battle of Maloyarovslavets. Then, crossing the Berezina river on temporary bridges which collapsed, another 25% were killed. 30% of the survivors died of cold, starvation, and exhaustion before finally crossing the Russian border on December 16th. The total percentage of soldiers in Napoleon's army killed during the Russian campaign was therefore…

A whale, elephants, and baby hippopotami

Let e, h and b be the respective weights of one elephant, one baby hippopotamus, and one whale (in kg). We have:

5e + h = w ; e + 50 = 12h. and 200 + 11h = e.

The weight of an elephant can thus be written in two ways:

e =200 + 11h. or e =12h – 50.

w = 5e + h = 14 750 + 250 = 15 000 kg.

A Russian campaign
The percentage of survivors after each disaster totals:
78% x 92% x 94% x 95% x 96% x 75% x 70% = 32.3%.
Thus, the percentage of missing persons is:
100 – 32.3 = 67.7%.