When calculating probability you need to remember that probability is:
something that you are observing divided by total number of participants.
The number you get is relative value(has value between 0 and 1) and if you want to get it in percentage (more clearly) just multiply it with 100.
In this case we are observing blood type B persons. Number of them is 165.
Total number of persons is 1500. Therefore our calculation looks like this:
165/1500 = 0.11 or the probability is 0.11*100=11%
Let the smaller number = X
Then the larger number is 3x+4 ( four more than 3 times the smaller number)
The sum of both numbers = 80
so you have X + 3X+4 = 80
Simplify the left side:
4x+4 = 80
Subtract 4 from each side:
4x = 76
Divide both sides by 4:
X = 76/4
X = 19
The smallest number is 19
The largest number is 80 - 19 = 61 ( check: 3*19 = 57+4 = 61)
The two numbers are 19 and 61
If the question is 3^(2/3),
The answer is the cube root of 9.