How can you make number one disappear by adding something to it?

On 26-01-2022, Juli was murdered at her house in a city in India in the afternoon. There were three suspects in the murder and the following are the statements that were given by them:

John: I visited my village that day.
Jacob: I was out to deposit my house tax in the municipality office at that time.
Jonny: I was at a friend's place having lunch at that time.

Can you find out who is the murderer?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

No one wants to have it, but if one got it, he does not want to lose it. What is It?

There are three boxes of different sizes with three cupcakes inside each of the boxes in Christina's kitchen. At night her daughter wakes up and goes to the kitchen. She opens a box and eats all three cakes.

But in the morning Christina finds out that each box still had three cupcakes. How?

A Car driver was heading down a street in Washington. He went right past a stop sign without stopping, he turned left where there was a 'no left turn' sign and he went the wrong way on a one-way street. Then he went on the right side of the road past a cop car. Still, he didn't break any traffic laws. Why not?

This is a simple one. You just have to count the number of Fs in the given sentence.

Finished Files are the result of years of scientific study combined with the experience of years.

How many did you count?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

If all Goats are Sheep and all Sheep are Deers, are all Deers Goats ?