Volume 29
, Issue 1


You have (hopefully) learnt a little bit at school about geometric series, and have studied so-called 'limiting sums' of geometric series.

  1. Under what conditions is an increment of $\$b$ paid $k$ times a year [Option(B)] more advantageous than an annual increment of $\$a$ paid yearly [Option (A)]?

In the last issue of Parabola, the question was posed as to whether it is better to work for Company A (with an annual rise of $\$2,000$ or Company B (with only a six-monthly rise of $\$500$).

When overseas economists tackle the problem of supply and demand they like to talk about pig-iron, hogs and corn.

Esther Szekeres has provided us with a non-trigonometrical solution to Question 866.

Q.882 A triangle is divided by one straight line into two parts which are similar to each other. Prove that the triangle is isosceles or right-angled (or both).

Q.872 A flea on the number line jumps from the point $a$ to the point $b$, given by $a + \frac{1}{b} = 1$.