Ten Fibonacci numbers are split into three sets: A = {1, 2}, B = {3, 5, 8}, and C = {13, 21, 34, 55, 89}.

One number is chosen at random from each set. What is the probability that their sum is odd?

The rectangle shown consists of three large congruent squares, four small congruent squares, and a shaded rectangle. AB = 7 m and CD = 5 m.

What is the area of the shaded rectangle, in square meters?

A farmer had 16 cows. The first cow gave a litre of milk daily. The second gave two litres of milk daily, the third three litres daily and so on. Now, he wanted give away four cows to each of his four sons in such a way that the daily milk production of each of his sons is the same.

Can you provide a solution to the farmer?

Sara and Josh each threw 5 darts at the target shown.

Sara scored 19 points by landing 2 darts in A and 3 in B.

Josh scored 17 points by landing 1 dart in A and 4 in B.

How many points are given for a dart landing in A?

ColorADD is a labelling system for colour-blind people in which black and white symbols represent colours. It was devised by the Portuguese graphic designer Miguel Neiva, and has achieved success in Portugal, where you find the symbols on stationery, clothes and maps.

Here are four ColorADD symbols with the colours they represent.

a) Draw the symbols for red, yellow and brown.

b) The four colours below are dark purple, pink, silver and white. Match the colours to the symbols.

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c) What are the two possible symbols for grey?

Read more…Each box above the bottom row contains the sum of the two numbers right below it.

For example, the entry in box M is the sum of the entries in boxes A and B.

The sum of all the entries in Row 1 is 57.

The sum of all the entries in Row 2 is 85.

What is the entry in box X?

Read more…Can you change “100” to “CAT” by moving just two of these toothpicks?