Long difficult logic riddles

In a supermarket, the first 25 customers of the day purchased an average of two items each. After a further 15 customers, the average number of items purchased by each customer rose to eight. What was the average number of items purchased by the last 15 customers only?

A witch owns a field containing many gold mines. She hires one man at a time to mine this gold for her. She promises 10% of what a man mines in a day, and he gives her the rest. Because she is blind, she has three magic bags who can talk. They report how much gold they held each day, and this is how she finds out if men are cheating her. Upon getting the job, each man agrees that if he isn't honest, then he will be turned into stone. So around the witch's mines, many statues lay! Now comes an honest man named Garry. He accepts the job gladly. The witch, who didn't trust him said, "If I wrongly accuse you of cheating me, then I'll be turned into stone." That night, Garry, having honestly done his first day's job, overheard the bags talking to the witch. He then formulated a plan... The next night, he submitted his gold, and kept 1.6 pounds of gold. Later, the witch talked with her bags. The first bag said it held 16 pounds that day. The second one said it held 5 pounds. The third one said it held 2 pounds. Beaming, the witch confronted Garry. "You scoundrel, you think you could fool me. Now you shall turn into stone!" the witch cried. One second later, the witch was hard as a rock, and very grey-looking. How did Garry brilliantly deceive the witch?

There were two women, standing and facing the opposite ways. The first lady was facing south and the second lady was facing north. But, they could see each other. How is that possible?

An intelligent trader travels from one place to another with 3 sacks having 30 coconuts each. No sack can hold more than 30 coconuts. On the way, he passes 30 check points. At each check point, he has to give one coconut for every sack he is carrying. What is the maximum number of coconuts that he can have with him at the end of his journey?

There is a row of five different color houses. Each house is occupied by a man of different nationality. Each man has a different pet, prefers a different drink, and smokes different brand of cigarettes. The Brit lives in the Red house. The Swede keeps dogs as pets. The Dane drinks tea. The Green house is next to the White house, on the left. The owner of the Green house drinks coffee. The person who smokes Pall Mall rears birds. The owner of the Yellow house smokes Dunhill. The man living in the centre house drinks milk. The Norwegian lives in the first house. The man who smokes Blends lives next to the one who keeps cats. The man who keeps horses lives next to the man who smokes Dunhill. The man who smokes Blue Master drinks beer. The German smokes Prince. The Norwegian lives next to the Blue house. The man who smokes Blends has a neighbour who drinks water. Who has fish at home?

It was very dark. There was no electricity in the house. They had no candles or lanterns. The house was completely dark. A girl was reading and preparing for her exams. How?

Once upon a time there existed a temple in India which housed three identical idols which spoke to the devotees. The idols were of – God of Truth, which always spoke the truth; God of Falsehood, which always lied; and God of Diplomacy which sometimes spoke the truth and at other times lied. The pilgrims come from all parts of the world to get their questions answered by the Gods. But there was a problem. As the idols were indistinguishable, devotees were not sure from which idol to ask their questions and in turn they did not know which God has answered and whether to believe it or not. Once a wise man visited the temple. He asked the question: "Which God is seated at the centre?" to all the three idols. The idol on the left, centre and right replied God of Truth, God of Diplomacy and God of Falsehood respectively. The wise man at once proclaimed that he had solved the mystery of the temple.

You and a friend are standing in front of two houses. In each house lives a family with two children. "The family on the left has a boy who loves history, but their other child prefers math," your friend tells you. "The family on the right has a 7-year old boy, and they just had a new baby," he explains. "Does either family have a girl?" you ask. "I'm not sure," your friend says. "But pick the family that you think is more likely to have a girl. If they do have a girl, I'll give you $100." Which family should you pick, or does it not matter?

A man puts on a clean shirt every night before bed. On the first nigh he puts on a blue shirt. He than sleeps for 5 hours. Every one hour more he sleeps than the night before he put on a different color shirt the next night according to this scale: blue, black, red, green, white, pink, orange, brown, purple, yellow, grey, neon green, tan, and teal. Every one hour less he sleeps than the last night he put on a different color shirt the next night going backwards on his scale. If he were to wear a blue shirt because he slept more hours than the last night he does. If it was because he slept less hours than the night before he skips it and wears a teal shirt instead. If he goes backwards on the scale and goes to blue but would not wear a blue shirt he still counts blue in his going backwards on his scale. The second night the man wears a blue shirt because he did not sleep any more or less hours than the last night. The man sleeps for six hours that night. The next night he sleeps for five hours. Night number four he sleeps for eight hours. The next night he sleeps for seven hours. The next night he sleeps so well he sleeps for 11 hours. Night number seven he stays up so late he only sleeps for four hours. The next night he is so tired he sleeps for eight hours. The next night he sleeps for eight hours again. Night number ten he sleeps for 14 hours because he is sick. Since he slept so long the last night he only sleeps for seven hours. The next night he is a little bit tired so he sleeps for eight hours. The night after that he had to do so much work he only slept five hours. The next night at work they let him out early and he slept for nine hours. The next night he slept for eight hours. And the last night the man did he slept for ten hours. The next night he put on a different color shirt according to his scale, but the next night he randomly picked a shirt. At what night will the man wear a blue shirt again?

A man eats dinner, goes up to his bedroom, turns off the lights, and goes to sleep. In the morning, he wakes up and looks outside. Horrified at what he sees, he hurls himself out his window to his death. Why does he do this?