# Blog

## Half past angle

By David Shaw, 14 November 2018

At half-past three, what is the angle between the hands of a clock?

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## A fish tank on the table

By David Shaw, 31 October 2018

Jenny had a short, wide fish tank. She wanted to change the water, so she put the fish tank on a table and put a tall bucket on the floor right underneath. She was about to get a hose and siphon the water into the bucket, but before she started, she did some measuring.

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## Tom’s quilt brainteaser

By David Shaw, 17 October 2018

Tom’s just finished sewing a quilt! It’s made of lots of equal-sized squares of fabric sewn together. Currently, it’s 12 squares long and six squares wide. Tom tried putting the quilt on his bed, but it’s the wrong shape.

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## Making change

By David Shaw, 3 October 2018

Australia has six coins that are commonly used – 5 cents, 10 cents, 20 cents, 50 cents, $1 and $2. How many different ways can you make exactly 50 cents in Australian coins?

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## Planning to party

By David Shaw, 19 September 2018

On Sunday, 1 January, Latda announced her New Year’s resolution. “Throughout this year, on the fifth Sunday of the month, I’ll throw a party!” How many fifth Sunday parties did Latda celebrate that year?

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## Peter’s staircase

By David Shaw, 5 September 2018

Peter’s just finished building a new staircase up to the attic. It just fits along the four-metre-long wall of his lounge room, and it’s three metres tall. It has exactly 15 steps. Peter wants to have a carpet running along the staircase. How long does it need to be?

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## A list of letters

By David Shaw, 21 August 2018

Can you work out the next letter in this sequence? H, T, Q, F, S, S, E, N, … Hint: There are numbers lurking behind those letters. And as it grows, this sequence is shrinking!

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## Broken calculator

By David Shaw, 8 August 2018

Imagine your calculator is broken. Although it will still display numbers, only the 4 key, + key, = key and clear key work. Starting at 0, can you get the calculator to display 1000? What’s the fastest way, with the fewest button presses?

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## How old is my mum?

By David Shaw, 25 July 2018

Twenty years ago, my mum was twice my age. I’m 42 years old. How old is my mum?

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