By David Shaw, 28 November 2018
I have four different whole numbers written on a piece of paper. The largest number is four bigger than the smallest. The middle two numbers are even. If I add all four numbers together, I get 12. What are my numbers?
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By David Shaw, 14 November 2018
At half-past three, what is the angle between the hands of a clock?
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.
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.
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?
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?
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?
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!
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?
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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