Maths Challenge Puzzle

Maths related puzzles can provide a simple and focussed challenge - performing mental arithmetic as quickly as you can without making mistakes can actually be quite good fun!

Here are three maths challenge puzzles for you, an easy, a moderate and a hard puzzle. See if you can do them within a minute. The level of these is very fair with only a gentle increase in difficulty at each stage, so none of the calculations expected are unreasonable such as calculating 37.5% of a number or squaring 34! If you want harder ones, let me know.

Mental Arithmetic Pays, Literally

You can barely see a newspaper these days without having your mental arithmetic skills challenged.  Under the guise of a ‘mental gym’ a ‘maths challenge’ or similar, we are presented with a series of sums to perform.

Depending on your choice of newspaper, these can be fairly easy or almost impossible to really do in your head.  However, there are occasions where maths pays, or at least being able to approximate totals.

At the supermarket today I bought six things, and the bill seemed too high at £15.49 for them.  On leaving the supermarket I double checked and realised it was £2.88 too high as they had charged twice for a battery, when I had only bought one.

So mental arithmetic, or at least approximating what the total would be in my head, saved me £2.88.  Here are the prices of what I actually bought - what would your approximation of the total of these be as you were going around?

Magazine: £3.25; Battery: £2.88, Greeting card: £1.49, Chocolates: £3.66, Pastry: £0.89, Paper: £0.60