Terms & Conditions
Take a normal piece of paper, exactly 0.1 mm thick.
Fold it in half, and then in half again, and again, and again.
Do this a total of 50 times.
How thick would the final paper be (if this could be done)?
Hint: We'll assume that we can actually fold it this many times.
Very thick indeed! The paper doubles in thickness with each fold. If we could fold it 50 times, it would be around 70 million miles thick!
1 fold would be 0.1 + 0.1 = 0.1 x 2 ^ 1 = 0.2 mm
2 folds would be 0.1 + 0.1 + 0.1 + 0.1 = 0.1 x 2 ^ 2 = 0.4 mm
10 folds would be 0.1 x 2 ^ 10 = 102.4 mm
50 folds would be 0.1 x 2 ^ 50 = 112,589,990,684,262.4 mm = 112,589,990.7 km (around 70 million miles).
Using the letters EEEENNNNPPSS complete this grid. The grid reads the same across as down.
Answer: There are four boys and six girls in the family.
If there were B boys, and G girls we know that Daniel has twice as many sisters as brothers, so 2 x (b - 1) = g.
And his sister, Jessica, has one more sister than she has brothers, so g - 1 = b + 1.
2(b - 1) = g 
g - 1 = b + 1 
Using  in  gives:
2(b - 1) - 1 = b + 1
Expanding the bracket gives:
2b - 2 - 1 = b + 1
Simplifying the left hand side gives:
2b - 3 = b + 1
Add 3 to each side gives:
2b = b + 4
Subract b from both sides gives:
b = 4
Using b = 4 in  gives:
2(4 - 1) = g
6 = g