Irish Times Maths Week Poster 2025

Published on 14 October

This Maths Week Poster is available with the Irish Times on 14 October 2025.

Puzzle solutions will be released on this page at 12 noon.

One side contains puzzles and games to give your brain a good workout and the reverse is an attractive poster celebrating Ada Lovelace Day and exploring algorithms and AI.

Maths Week Ireland is an annual all-Island celebration of mathematical thinking. A basic proficiency in maths is necessary in daily life. Basic maths is needed in most jobs and a higher level of maths opens the door to many rewarding careers. Mathematics is particularly useful in describing behaviour of the natural world and helps us understand and predict impacts of such things as the climate emergency and pandemics.

Maths Week was founded by Calmast, the STEM Engagement Centre at South East Technological University.

For more information see www.mathsweek.ie

Puzzle Solutions 2025 Poster

Money Sense

Vending Machine

1). Ciara bought a drink and an apple (€3 + €0.88 = €3.88)

2). Liam bought a drink and two chocolate bars (€3.00 + 2x€1.75 = €6.50)

3). Lisa bought a drink and four apples (€3.00 + 4x€0.88 = €6.52)

Coins

1) . Brian gets €6 (half of €12)

2). €2 (a third of €6)

3). €4 (€6 – €2)

Coffee and Muffins

Coffee = €2

Muffin = €1.50

Foodcloud Puzzles

The correct Hallowe’en route was

The locker code is 6 2 3 1

Tá na digití don chód: 9 7 0 8

“Word Puzzles” Short Questions

  1. What is my age? It has two digits. They sum to 9. The second digit is twice as big as the first digit.
  1. Four friends meet up for coffee. They find that the average of their ages is 40. One of them leaves and the average of the remaining three drops to 38. How old was the friend who left?
  1. In a family the girls have the same number of sisters as brothers, but the boys have twice as many sisters as brothers. How many siblings are there?
  1. If it takes 2 pupils 2 minutes to do two sums, how many sums will 4 pupils do in 4 minutes?
  1. If it takes 3 minutes to boil 1 small egg and 4 minutes to boil 1 large egg, how many minutes would it take to boil 1 large and 2 small eggs?
  1. If two coffees and one brownie costs €11 and two brownies and one coffee costs €10, How much does one brownie cost?
  1. What’s twice one half of one fifth of 20?
  1. Passing a window, you see an item you would like priced at €100. The following week you see that the item has been marked up by 20%. A week later there is a sale and you see that all items are reduced by 20% on the marked prices. When was the best time to buy the item?
  1. If you have 12 white socks and 8 black socks in a drawer, how many would you have to pull out to be sure of having a matching pair.
  1. Here is a longer one and you can try a higher target if you like a bigger challenge. Using each of the numbers 2,4,6,8 (once and only once) and the four operators, addition, subtraction, multiplication and division can you make the numbers 0 – 10?

Solutions:

(1) 36,

(2) 46,

(3) 7 – 3 boys, 4 girls,

(4) 8 minutes,

(5) 4 minutes,

(6) €3,

(7) 4,

(8) In the sale at €96,

(9) 3,

(10)

Here are some ways it can be done – perhaps you have found others.

(I have used a lot of parentheses to make them extra clear)

(6+4) – (8+2) = 0

(6+4)/(8+2) =1

6 – (8/4) -2 = 2

6/(8-4-2) = 3

4 + (8-6-2) = 4

((2×6) + 8) /4 = 5

6 + (8 – (2×4)) = 6

6 + (2×4)/8 = 7

8 + (6-4-2) = 8

8 + (2+4)/6 = 9

6 + (8/4) + 2 = 10