# Maths prize: casting out nines

The first ever printed maths book, as far as we know, was the “Treviso Arithmetic”, printed in Treviso, near Venice, in Italy, in 1478. A printed edition of Euclid’s “Elements” came out soon after, in 1482. Unlike Euclid, where everything is proofs, the Treviso Arithmetic was a collection of practical ideas to do or check calculations.

# Fortnightly maths prize for 7 July

Nearly 100 years ago, the great mathematician Srinivasa Ramanujan was ill in hospital. His friend G H Hardy, professor of maths at Cambridge, went to visit him. Continue reading

# Fortnightly maths prize for 23 June

No-one attempted this one, which I guess is due to it being post-exam time rather than it being specially difficult.

Part 1:

Part 2:

Find the sum to n terms of the first n numbers multiplied pairwise

For n = 3 it is 1×2 + 1×3 + 2×3, which makes 11

Your job is to find a general formula which works for any n.

# Maths prize: Russian peasant boys (1 December 2015)

The painting above, done in 1895, is of Russian peasant boys doing a mental arithmetic puzzle. As you can see, one of them has the answer and is whispering it into the teacher’s ear. Continue reading

# Fortnightly maths prize for 24 March

Sharif Quansah and Hayden Leroux won prizes for partial answers.

The problem: Calculate the remainder when 23 is divided by 3
when 25 is divided by 5
when 27 is divided by 7
when 35 is divided by 5
when 37 is divided by 7
when 45 is divided by 5 Continue reading