Find the Next Number in the Sequence

2 9 3 1 8 4 3 6 5 7 ?

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

Count the number of triangles in the picture below:

John went to meet his friend Jacob, but when he was about to reach the main gate, John notices that Jacob had a mighty dog who was fastened to the tree. The chain is long enough that it allows the dog to reach the main gate.

How can the John reach the main gate?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

A beggar on the street can make one cigarette out of every 6 cigarette butts he finds. After one whole day of searching and checking public ashtrays the beggar finds a total of 72 cigarette butts. How many cigarettes can he make and smoke from the butts he found?

How many sides does a circle have?

Identify the 10 differences between the two given pictures.

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?