1/4 = 5/20
2/5 = 8/20
8/20 + 5/20 = 13/20 has been spent
There are 25 species of trees, each with a known abundances. The question is how many possible ways to randomly select one tree there are.
We should calculate the number of combinations. Combinations, because we select item/s from a collection. In this case, when we select only one item, the combination is also a permutation. From set of n objects we select r. In our case: n=25, r=1.
The equation is: n!/r!(n-r)!= 25!/1!*24!=25*24!/24!=25
There are 25 different outcomes (events).
Answer:
(d) 0.8736
Step-by-step explanation:
Unless you have a table of the normal distribution available, this is a calculator problem. Your calculator, or any spreadsheet, can tell you the probability is ...
P(-1.23 ≤ z ≤ 2.12) ≈ 0.8736
Answer:
81 maybe not sure
Step-by-step explanation:
Step-by-step explanation: