Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

All of Jacob's shoes are red except two.
All of Jacob's shoes are green except two.
All of Jacob's shoes are yellow except two.

How many shoes does Jacob have?

In case you were starting to feel confident, this one was meant for third graders in Vietnam. The answer is 66, but we don't blame you for scratching your head about how they got there.

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

Using mathematical symbols like +, -, and x in order to make the equations correct. Replace # with the above-given symbols.

9 # 8 # 7 # 6 # 5 # 4 = 91

Can you write down eight eights so that they add up to one thousand?