What is common among 11, 69, and 88?

How many triangles are there on the puzzle below?

The cream is heavier than Milk. True or False?

There are 3 apples in the basket and you take away 2. How many apples do you have now?

What is the centre of gravity?

If one and a half boys, eat one and a half burgers in one and a half hours.

How many burgers can 9 boys eat in 3 hours?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

How can you leave a room with two legs and return with six legs?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

I am the largest in my family of fifty.
The youngest of our family lives separately from the rest of the family and so do I.
I am regarded as harsh and tough.
I am so large, you cut me in two equal halves,
each half would still be larger than the second largest member of the family.
Who am I?