Answer:
13, 14, 15, 16
Step-by-step explanation:
Call the first number n. Then the next three consecutive numbers (assuming integers) are n + 1, n + 2, n + 3.
The mean is the total of the numbers divided by how many there are.

Simplify and multiply by 4.

The first number is 13.
The median is 14.5, halfway between the "middle" numbers 14 and 15. This is just a check; no additional equation is necessary.
For each of the 3 choices of hat there are 2 choices of shorts. Therefore there are 3 * 2 combinations of hat and shorts. Each of these 3 * 2 combinations of hat and shorts can be combined with each of the 5 choices of shirt.
Therefore the number of combinations of 1 hat, 1 shirt and 1 pair of shorts is given by:
if indeed DEF is a right-triangle, then we can apply the pythagorean theorem and the hypotenuse is really the square root of the sum of the square of the other two, if however the hypotenuse doesn't equal that, then is not,

-1/2 is rational, have a good day