Solution:

5832/17496
This fraction will give the desired result i.e. 1/3.

Solution:

3^2 = 4 + 5
(^ is used for squaring the term, it is not used here as a mathematical symbol.)

Solution:

10992

Explanation:
Each girl has seven bags with seven adult cats each.
Also, each adult cat has seven little cats.
Thus each girl has 49 adult cats and 343 little cats.

Hence, seven girls will have
343 adult cats and 2410 little cats.

If we calculate the number of legs now.
Girls = 7 * 2 = 14
Cats + Little cats = 2744 * 4 = 10976

Total legs = 10976 + 14 = 10990

Since I also walked in the room, there will be two more legs.
Now total legs = 10990 + 2 = 10992.

Solution:

He will hang clock number 315 at 7:30pm. The person has been hanging the clock number which corresponds with the angle between the hour hand and the minute hand of the clock at that time.

Solution:

We know that there may be many possibilities and if you find one it is great. For reference we have given one solution below.

(1 + (3 + 4*5)*6)*2

Solution:

On multiplying all the 6 pairs we get (a*b*c*d)^3.
Assuming the missing product is a*b, then amid the 5 given products we see (a*c)*(b*d)=(a*d)*(b*c)
If we look at the numbers clearly 5 is out of the equation because there is nothing to balance it so the only remaining match is 2*6=3*4, so a*b*c*d=2*6=12.
So the product of all 6 pairs should be 12^3, the product of the given 5 is 720, so the missing one is 12/5=2.4

Solution:

88 + 88/88

Solution:

8

Solution:

125874 => 251748

251748 is twice the 125874 and have same digits 1,2,4,5,7 & 8

Solution:

3