A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

There is one four-digit whole number n, such that the last four digits of n2 are the original number n

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

What does the below mathematical rebus mean?

I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

Can you find the six hidden animals in the picture below?

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Sally lives in a place where six months of the year is mild summer and the temperature drops significantly the other six months. She owns a lake where there is a small island. She wants to build a house on the island and needs to get materials there. She doesn’t have a boat, plane, or anything to transport them to the island. How does Sally solve this problem?

Solve the puzzle by telling what does below picture means.