A prime number is a number which has no factors except 1 and itself.
Another Hint
In your list, Pete will be number three.
Answer
You already know how long the head is (60cm). Next, look at the clue which tells you how long the tail is.
Another hint
This problem is best set out like this: 36
4 = answer
Answer
Find a factor of 34 which is not a factor of 36 which has digits that add up to 8.
Answer
Remember: you know who the oldest and youngest brothers are. You only need to sort out the order of Pete, Bolly and Rick.
Another hint
A prime number is a number which has no factors except 1 and itself.
Another Hint
The correct factor is in this list:
Factors of 12: 1, 2, 3, 4, 6, 12
Factors of 21: 1, 3, 7, 21
Answer
The correct factor is in this list:
Factors of 34: 1, 34, 2, 17
Factors of 36: 1, 36, 3, 12, 2, 18, 4, 9, 6
Another hint