A Japanese ship was en route to a mission on foreign seas. The captain of the ship felt tired and thought of taking a bath. He went for taking the shower and removed his diamond ring and Rolex and kept them on the table. When he returned after taking the bath, he found that the ring and watch were stolen.
He called the five members of the crew whom he suspected and asked them what they were doing for the last 15 minutes.
The Italian cook (with a butcher knife in hand): I was in the fridge room getting meat for cooking.
The British Engineer (with a high beam torch in hand): I was working on a generator engine.
The Pakistani seaman: I was on the mast correcting the flag which was upside down by mistake.
The Indian Radio officer: I was trying to make a contact with the company to inform them about our position.
The American navigation officer: I am on night watch, so I was sleeping in my cabin.
Upon listening to them, the captain caught the lying member. Who do you think stole the valuables?
Take number 1000 and then add 20 to it.
Now add 1000 one more time.
Now add 30.
Now add 1000 one more time.
Now add 40.
Now add 1000 one more time.
Now add 10.
Your job is to measure 45 minutes if you have only two cords and matches to light the cords.
1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.