Our product and our sum always give the same answer. Who are we?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

What has 13 hearts but no other organs?

Find the next number in the series below

21 32 54 87 131 ?

On my way to St. Ives I saw a man with 7 wives. Each wife had 7 sacks. Each sack had 7 cats. Each cat had 7 kittens. Kittens, cats, sacks, wives. How many were going to St. Ives?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

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?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

Some friends went on a vacation to a resort. It was raining heavily and it kept raining for thirteen days.

When it rained in the morning, the afternoon was beautiful and when it rained in the afternoon, the day was blessed with a clear morning.

Overall, the friends experienced eleven nice mornings and twelve nice afternoons. Can you find out the number of days they spent on vacation?

Why do we preferably have round manhole covers and not square ones?