Random Puzzles 

Workings

Hint
This question involves the months of the year in some way.

Answer
4 3 1.

Reasoning
This is the sequence of the length of the name of the month, and the number of days in that month.

7 3 1 = January, which has 7 letters, and 31 days.

8 2 8 = February, which has 8 letters, and 28 days.

5 3 1 = March, which has 5 letters, and 31 days.

5 3 0 = April, which has 5 letters, and 30 days.

3 3 1 = May, which has 3 letters, and 31 days.

4 3 0 = June, which has 4 letters, and 30 days.

Which means the next three digits are:

4 3 1 = July, which has 4 letters, and 31 days.

Workings

Hint
How much petrol was used for the journey itself?

Answer
3 gallons each hour.

Reasoning
I drove 300 miles at 30 miles per gallon, so I used 10 gallons. Which means I lost the other 15 gallons.

I drove the 300 miles at 60mph, which took me 5 hours.

So I lost 15 gallons of petrol in 5 hours = 3 gallons per hour.

Workings

Hint
Neptune is written diagonally.

Answer
 

Workings

Hint
The final word starts with AI.

Answer
Isle becomes aisle.