A website Maths Puzzle

There are 2 trees in a garden (tree "A" and "B") and on the both trees are some birds.

The birds of tree A say to the birds of tree B that if one of you come to our tree, then our population will be the double of yours.

Then the birds of tree B tell to the birds of tree A that if one of you come here, then our population will be equal to that of yours.

Q. How many birds in each tree?

Read Solution (Total 9)

A website Other Question

Q. What is the next term in this sequence?

1, 11, 21, 1211, 111221,... ?
In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctly.

Q. How many people have guessed three fruits correctly, and how many people have guessed four fruits correctly?..