Probability of rolling a sum of 9 or a sum that is even from two number cubes is 11/18 Explanation: When a dice is rolled there are different ways in which 9. can be obtained, which are (3,6) or (4,5) or (5,4) or (6,3). 4 options. As in all there are 6⋅6=36 options, probability is 4/36 or 1/9.
For getting an even number as sum, we can have (1,1) or (1.3) or (1,5) or (2,2) or (2,4) or (2,6) or (3,1) or (3,3) or (3,5) or (4,2) or (4,4) or (4,6) or (5,1) or (5,3) or (5,5) or (6,2) or (6,4) or (6,6) 18 options, probability is 18/36 or 1/2.
Note that the two events (getting 9 or even sum) are mutually exclusive, the probabilities can be just added i.e. combined probability is 1/9+1/2=2+9/18i.e. 11/18
From 10 to 15 -> 10 increased with half its size (5), that means increase of 50% From 16 to 12 -> decrease of 4, which is a quarter of 16, that means a decrease of 25%
First you would subtract 2 to get d/3 by itself. On the left side you would have h-2 and one the right d/3 (h-2=d/3). Then you divide by 3 to get d by itself. So the answer is h/3-2/3=d
