Logic Puzzles with Solutions

Puzzle 1: How do you cut a circular cake into eight equal pieces in just 3 cuts?

Puzzle 2: You have a 3 liters and a 5 liters measuring jug. How are you going to get 4 liters from it?

Puzzle 3: You have 10 sets of 10 metal balls. You know the balls should weigh 10 g each. You know the balls in 1 set are exactly 1 g lighter. You are allowed to use an extremely accurate digital weighing scale only once. How do you determine which set of balls is lighter?

Puzzle 4: You have to fill the boxes with numbers from 1-8 by following below mentioned rules.
Rule 1: Predecessor and successor can’t be besides. Example if we take number 3 in any box, than neither side of 3 can have 2 or 4.
Rule 2: Predecessor and successor can’t be upside or downside. Example: if we take 3 in any box, then the box above can not have 2 or 4, similarly box below can not have 2 or 4.
Rule 3: Predecessor and successor can’t be diagonally either.

Puzzle 5: A Farmer had to cross a river, he had a Dog, a Chicken and some Corn. The Dog will bite the Chicken and the Chicken will eat the Corn if the Farmer is not around. The Farmer can only take 1 out of the 3 on the boat when crossing the river. How the Farmer can cross the river?

Puzzle 6: A dysfunctional family has to cross the river. On one side of the river are a Mother and 2 Daughters, Father and 2 Sons, the Maid and the Dog. There is a boat only big enough to hold 2 people (counting the dog as 1 person). Only the adults are capable of operating the boat. Everyone has to get to the other side, without anything bad happening.
Now the difficulties are : if the Dog is left with anyone and the Maid isn’t there to control him, he’ll bite. The Father can’t be left with any of the Daughters when the Mother isn’t there. Likewise, the Mother can’t be trusted alone with either of the Sons when the Father isn’t there.
Remember! only an adult can operate the boat, and the boat can’t drive itself.

Puzzle 7: A Cowboy need to cross the river with 4 Horses, he can only ride 1 and pull 1 when he cross. The Horses cross river at different speed, A require 1 minute, B require 2 minutes, C require 5 minutes and D require 10 minutes. The duration of the crossing will be the slowest Horse. If base on this logic, he cross with riding A and pulling the remaining Horses will be take 19 minutes in total as follows: A and B cross = 2 minutes, A come back = 1 minute, A and C cross = 5 minutes, A come back = 1 minute, A and D cross = 10 minutes. 2 + 1 + 5 + 1 + 10 = 19 minutes. But there is a way that he can complete the task at a shorter duration. Can you figure it out?

Puzzle 8: You got 8 eggs, 1 egg is spoil. The spoil egg is lighter than the other eggs. You can use a balancing scale only 2 times. Can you find out which egg is spoil?

Puzzle 9: You got 9 eggs, 1 egg is different. You do not know if the  egg is lighter or heavier than the other eggs. You can use a balancing scale only 3 times. Can you find out which egg is different?






Solution 1: Using 2 cuts to cut the cake into 4 equal pieces from the top, then using the 1 more cut to cut horizontally and you will get 8 equal pieces.


Solution 2: Fill the 5 liters jug. 
Pour 3 liters into the 3 liters jug with 2 liters remaining in the 5 liters jug. 
Empty the 3 liters jug. 
Pour the remaining 2 liters from the 5 liters jug into the 3 liters jug. Fill the 5 liters jug again. 
Pour 1 liter from the 5 liters jug into the 3 liters jug. 
Now the 5 liters jug will contains 4 liters.

Solution 3: Take 1 ball from the first set along with 2 balls from the second set and go on until you take 10 balls from the tenth set. If all the balls are 10 g you should get 550 g for 55 balls. If the weight is lighter by 1 g then it is the first set that is lighter, if the weight is lighter by 2 g then it is the second set which is lighter. By the reduce of weight you will be able to determine the set which is lighter.

Solution 4: 

Solution 5: The Farmer bring the Chicken cross the river.
The Farmer come back.
The Farmer bring the Dog cross the river.
The Farmer bring the Chicken back.
The Farmer bring the Corn cross the river.
The Farmer come back.
The Farmer bring the Chicken cross the river.

Solution 6: Maid and Dog cross first, and the Maid comes back.  
Maid and 1 Son cross, Maid and Dog come back. Father and another Son cross, Father comes back.
Mother and Father cross, Mother comes back.
Maid and Dog Cross, Father comes back.
Mother and Father cross, Mother comes back.
Mother and 1 Daughter cross, Maid and Dog come back.
Maid and another Daughter cross, Maid comes back.
Maid and Dog cross.

Solution 7: A and B cross = 2 minutes, A come back = 1 minute, C and D cross = 10 minutes, B come back = 2 minutes, A and B cross = 2 minutes. 2 + 1 + 10 + 2 + 2 = 17 minutes. 

Solution 8: Put 3 eggs on each side of the balance. 
If the scale tilt then the spoil egg is in the side which is higher. 
Take 2 eggs from the 3 eggs and put 1 egg on each side of the balance.
If the scale tilt then the spoil egg is in the side which is higher.

If the scale balance then the spoil egg is the remaining egg.
If the scale balance at first try then the spoil egg is in the remaining 2 eggs.
Take the 2 eggs and put 1 egg on each side of the balance.
The scale tilt with the spoil egg is on the side which is higher. 

Solution 9: Put 3 eggs on each side of the balance. 
If the scale tilt switch the remaining 3 eggs with the side which is higher.
If the scale still tilt, the egg is heavier and it is in the lower side.
If the scale balance, then the egg is lighter and it is in the set which you had just switch.
Take 2 eggs from the 3 eggs and put 1 egg on each side of the balance and you will be able to find the egg.

Science and Religion Logics

A professor of philosophy speaks to his class on the problem science has with God.
He asks one of his new students to stand and.....

Prof: So you believe in God?

Student: Absolutely, sir.

Prof : Is God good?

Student: Sure.

Prof: Is God all-powerful?

Student : Yes.

Prof: My brother died of cancer even though he prayed to God to heal him. Most of us would attempt to help others who are ill. But God didn't. How is this God good then? Hmm?

(Student is silent.)

Prof: You can't answer, can you? Let's start again, young fella. Is God good?

Student: Yes.

Prof: Is Satan good?

Student : No.

Prof: Where does Satan come from?

Student: From...God.. .

Prof: That's right. Tell me son, is there evil in this world?

Student: Yes.

Prof: Evil is everywhere, isn't it? And God did make everything. Correct?

Student: Yes.

Prof: So who created evil?

(Student does not answer.)

Prof: Is there sickness? Immorality? Hatred? Ugliness? All these terrible things exist in the world, don't they?

Student: Yes, sir.

Prof: So, who created them?

(Student has no answer.)

Prof: Science says you have 5 senses you use to identify and observe the world around you. Tell me, son...Have you ever seen God?

Student: No, sir.

Prof: Tell us if you have ever heard your God?

Student: No, sir.

Prof: Have you ever felt your God, tasted your God, smelt your God? Have you ever had any sensory perception of God for that matter?

Student: No, sir. I'm afraid I haven't.

Prof: Yet you still believe in Him?

Student: Yes.

Prof: According to empirical, testable, demonstrable protocol, science says your GOD doesn't exist. What do you say to that, son?

Student: Nothing. I only have my faith.

Prof: Yes. Faith. And that is the problem science has.

Student: Professor, is there such a thing as heat?

Prof: Yes.

Student: And is there such a thing as cold?

Prof: Yes.

Student: No sir. There isn't.

(The lecture theater becomes very quiet with this turn of events.)

Student : Sir, you can have lots of heat, even more heat, superheat, mega heat, white heat, a little heat or no heat. But we don't have anything called cold. We can hit 458 degrees below zero which is no heat, but we can't go any further after that.
There is no such thing as cold . Cold is only a word we use to describe the absence of heat.
We cannot measure cold. Heat is energy . Cold is not the opposite of heat, sir, just the absence of it .
(There is pin-drop silence in the lecture theater.)

Student: What about darkness, Professor? Is there such a thing as darkness?

Prof: Yes. What is night if there isn't darkness?

Student : You're wrong again, sir. Darkness is the absence of something. You can have low light, normal light, bright light, flashing light....But if you have no light constantly, you have nothing and it's called darkness, isn't it? In reality, darkness isn't. If it were you would be able to make darkness darker, wouldn't you?

Prof: So what is the point you are making, young man?

Student: Sir, my point is your philosophical premise is flawed.

Prof: Flawed? Can you explain how?

Student: Sir, you are working on the premise of duality. You argue there is life and then there is death, a good God and a bad God. You are viewing the concept of God as something finite, something we can measure. Sir, science can't even explain a thought. It uses electricity and magnetism, but has never seen, much less fully understood either one. To view death as the opposite of life is to be ignorant of the fact that death cannot exist as a substantive thing. Death is not the opposite of life: just the absence of it.

Now tell me, Professor. Do you teach your students that they evolved from a monkey?

Prof: If you are referring to the natural evolutionary process, yes, of course, I do.

Student: Have you ever observed evolution with your own eyes, sir?

(The Professor shakes his head with a smile, beginning to realize where the argument is going.)

Student: Since no one has ever observed the process of evolution at work and cannot even prove that this process is an on-going endeavor, are you not teaching your opinion, sir? Are you not a scientist but a preacher?

(The class is in uproar.)

Student: Is there anyone in the class who has ever seen the Professor's brain?

(The class breaks out into laughter.)

Student : Is there anyone here who has ever heard the Professor's brain, felt it, touched or smelt it? No one appears to have done so. So, according to the established rules of empirical, stable, demonstrable protocol, science says that you have no brain, sir.
With all due respect, sir, how do we then trust your lectures, sir?

(The room is silent. The professor stares at the student, his face unfathomable. )

Prof: I guess you'll have to take them on faith, son.

Student: That is it sir... The link between Man & God is FAITH . That is all that keeps things moving alive.