For the numeric part, you'll have to find the GCD of 15 and 25, which is 5. So, we can factor a 5 and we have
As for the literal part, you can factor 
because it's the power of s with the smallest denominator. So, we have
Answer:
First we need to calculate the are of each wall, since we alredy knew the length (l) and the width (w) which is the height of the wall in this case:
A = wl = 9 . 12 = 108 (ft²)
We also know that he painted 3 walls, we need to multiply our first result by 3, in other words, the area of wall that Brett painted is the sum of the area of three walls: 108 . 3 = 324 (ft²)
1/4 because 6/24 can be simplified all the way down to 1/4
It would be 12:00 in London if its 13:00/1:00 in South Africa
