What is the next number in the series?

15 29 56 108 208 ?

Name a key which is hardest to turn.

Move three sticks of the spiral below to form a square.

I am 5 letters long.
My first two tell you who I am
My first 3 could be a medicine
My last three reversed could be a young boy.
My 4th, 3rd and 2nd in that order could be a fruit drink.
If you have me you may hang me round your neck
WHAT AM I ?

Find the mistake in the below maths equations

A = 2
A(A-1) = 2(A-1)
A2-A = 2A-2
A2-2A = A-2
A(A-2) = A-2
A = 1

Can you spot the hidden girl in the picture below?

Complete the following series. It.s very logical:

1, 4, 5, 6, 7, 9, 11, __?

Why Wine Glass Stem is so long?

I have an apple tree , number of apple in this tree get doubles every week.

On 30th week , the tree gets completely filled with apples :-)



Can you tell me , on what week does my tree is half covered with apples ?

How many words can a pen with half refill write?