Vanessa, a research director, is conducting an experiment to determine the effectiveness of treatment for peach trees against blight. She randomly divides one grove's trees into three groups. One group is the control with no treatment for blight. She prunes the second group to remove the limbs showing blight after the spring rains. She prunes the third group as well and also sprays them with an antibiotic. Vanessa monitors the trees were monitored for five years after the start of the experiment. The following table shows the outcomes, or the counts of how long the trees in each group lived. Treatment Outcomes None Pruning Antibiotic Totals 0 to 2 years 39 35 27 101 2 to 4 years 28 44 44 116 More than 4 years 13 25 51 89 Totals 80 104 122 306 What is the probability that a randomly selected tree from this experiment lived two to four years or was treated with an antibiotic?

Vanessa, a research director, is conducting an experiment to determine the effectiveness of treatment for peach trees against blight. She randomly divides one grove's trees into three groups. One group is the control with no treatment for blight. She prunes the second group to remove the limbs showing blight after the spring rains. She prunes the third group as well and also sprays them with an antibiotic. Vanessa monitors the trees were monitored for five years after the start of the experiment. The following table shows the outcomes, or the counts of how long the trees in each group lived. Treatment Outcomes None Pruning Antibiotic Totals 0 to 2 years 39 35 27 101 2 to 4 years 28 44 44 116 More than 4 years 13 25 51 89 Totals 80 104 122 306 What is the probability that a randomly selected tree from this experiment lived two to four years or was treated with an antibiotic?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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	Treatment
Outcomes	None	Pruning	Antibiotic	Totals
0 to 2 years	39	35	27	101
2 to 4 years	28	44	44	116
More than 4 years	13	25	51	89
Totals	80	104	122	306

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