Answer:
34,220
Step-by-step explanation:
Because order doesn't matter, but the numbers can't be repeated, we need to find the number of combinations where 3 individual numbers can be chosen out of 60 possible numbers using the binomial coefficient:

Thus, Elias can make 34,220 unique 3-number codes given 60 different numbers.
She should use a computer to select 30 students at random then ask which ones play chess. The other options could produce more skewed results.
The distance between the numbers increases by two every interval
for example, the difference between 1 and 2 is 1, if you add 2 you get 3, and the difference between 2 and 5 is 3
hope this helped!
Ok sweetheart, the easy way to solve these problems is to change them to all the same form for example "decimal" after that you sort them! just don't forget to remember which is which!!! so this is how you solve.
squared 25, 4.26, 3 1/5 2^3,2.58
i converted each so your answer is A.