What is always in front of you but can’t be seen?

The more of this there is, the less you see. What is it?

John was piloting a plane behind a car but was never able to overtake it. Why?

There is a hypothetical state between the USA and Mexico border 'Tango'.
Here 70 percent of the population have defective eyesight, 75 percent are hard of hearing, 80 percent have Nose trouble and 85 percent suffer from allergies, what percentage (at a minimum) suffer from all four ailments?

Using Only Five 5's and any mathematical operator make sum as 37

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

what one word does the below rebus identifies?

In the image given, you can find several triangles. Can you count them all?

Arrange the numbers 1, 2, 3, 4, 5, 6, 7, 8 and 9 above and below the division line in a manner that the thus formed fractions equal to 1/3.

(You can use one number only once)

How many sides does a circle have?