3^-2 = 0.111111111 ← Answer
Based on the venn diagram of siblings, the probability of having a brother and sister is c. 0.33.
<h3>What is the probability of brother and sister?</h3>
The probability of having a brother and sister can be found as:
= Number of those with brother and sister / Total number of people in poll
Solving gives:
= 10 / (8 + 10 + 5 + 7)
= 10 / 30
= 0.33
In conclusion, the probability of having a brother and sister is 0.33.
Find out more on Venn diagrams at brainly.com/question/9085273
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