10ticks Friday Puzzle

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This week's Friday Puzzle


a = 1, b = 2, c = 3,........, z = 26


(n - a)(n - b)(n - c) .... (n - z).

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Friday Puzzle (13/04/2018)

Students and spiders:

10 heads and 56 legs.

How many students?

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Friday Puzzle (06/04/2018)

I have a 2-digit number. If the order of the digits is changed, it makes a new number, which is one less than half of my number.

What is my number?

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Friday Puzzle (23/03/2018)

Five squares are drawn on the sides of a pentagon as shown.

pentagon and square

What is the sum of the five angles marked in red?

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Friday Puzzle (16/03/2018)

Lynne: “Jane is innocent” 
George: “Tim is guilty” 
Jane: “George is guilty” 
Tim: “Lynne is innocent” 
Only the guilty person is lying; all the others are telling the truth.

Who is guilty?

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Friday Puzzle (09/03/2018)

The difference between 1/4 of a certain number and 1/5 of the same number is 3.

What is that number?

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Friday Puzzle (02/03/2018)

Find the positive integer, x, that satisfies the equation

√3  +  √12  +  √27  =  √x

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Friday Puzzle (23/02/2018)

The five equally sized rectangles are placed inside a square as shown.

Rectangles in Square

The square has a side length of 24 cm.

What is the area of one rectangle?

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Friday Puzzle (16/02/2018)

The three rectangles below all have the same area.


What is the value of x + y?

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Friday Puzzle (09/02/2018)

The largest of four different real numbers is x.

When the numbers are summed in pairs, the four largest sums are 13, 12, 10 and 9.

What are the possible values of x?

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