Solution:

Kid1, he was left with one rock.

Solution:

step 3 is wrong

Solution:

Four

three placed flat on the table in a triangle(touching each other) and put the fourth one on top of them in the middle.

Solution:

5 leopard and one sheep

since all animal are rational , once 1st leopard eats the sheep all the rest of leopard would know about this.

Solution:

12:00

both minute and hour clock lie exactly between the number one and two in the number.

Solution:

1. We open the cupboard, put the dinosaur in the cupboard and close it.
2. We should open the cupboard, take the dinosaur out of cupboard, put the tiger in and close it.
3. The tiger, hes still in the cupboard
4. You swim across the lake as all the crocodile are at the party.

Solution:

The mules is moving in circular path and hence outside legs travels more distance than inner legs.

Solution:

Steps:
1) Light fire on first bar from both the ends and second bar from one end.

2) After 30 seconds(when first bar gets completely burned out) , burn the second bar from second end as well.

3) When second run completely gets burned , you know its 45 seconds.

Solution:

Step 5 is invalid, because we are dividing by (x-y), and since x=y, we are thus dividing by 0. This is an invalid mathematical operation (division by 0), and so by not following basic mathematical rules

Solution:

'five'

Its the count of alphabet