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13 votes
Please answer this question immediatly

Please answer this question immediatly-example-1
Please answer this question immediatly-example-1
Please answer this question immediatly-example-2

2 Answers

8 votes

Apple be A and blueberries be B

So

As per Venn diagram

  • n(A)=12
  • n(B)=7
  • n(A$\cap$B)=3

#1

  • n(A)+n(B)
  • 12+7
  • 19

P(A)=12/24

P(B)=7/24

Add

  • 12+7/24
  • 19/24

#2.

n(AUB)

  • n(A)+n(B)-n(An B).
  • 19-3
  • 16

E=8+16=24

P(AUB)=16/24=2/3

User Rugnar
by
4.9k points
7 votes

Answer:


\sf a) \quad P(contains\:apple)+P(contains\:blueberry)=(5)/(6)


\sf b) \quad P(contains\:apple\:or\:blueberry)=(11)/(15)

c) Not mutually exclusive events

Explanation:

From inspection of the Venn diagram:

  • Total number of smoothies = 12 + 3 + 7 + 8 = 30
  • Number of smoothies containing Apple = 12 + 3 = 15
  • Number of smoothies containing Blueberry = 3 + 7 = 10
  • Number of smoothies containing both Apple and Blueberry = 3
  • Number of smoothies not containing Apple or Blueberry = 8


\sf Probability\:of\:an\:event\:occurring = (Number\:of\:ways\:it\:can\:occur)/(Total\:number\:of\:possible\:outcomes)

Let A = contains apple

Let B = contains blueberry


\implies\sf P(A)=(15)/(30)=(1)/(2)


\implies\sf P(B)=(10)/(30)=(1)/(3)

Part (a)


\begin{aligned} \implies \sf P(A)+P(B) & =\sf (1)/(2)+(1)/(3)\\\\ & = \sf (3)/(6)+(2)/(6)\\\\ & = \sf (5)/(6)\end{aligned}

Part (b)


\textsf{Addition Law}: \quad\sf P(A\:or\: B) = P(A)+P(B)-P(A\:and\:B)

Given:


\sf P(A)+P(B)=(5)/(6) \quad \textsf{(from part a)}


\sf P(A\:and\:B)=(3)/(30)\quad \textsf{(where the circles overlap)}


\begin{aligned}\implies \sf \sf P(A\:or\: B) &= \sf P(A)+P(B)-P(A\:and\:B)\\\\& =\sf (5)/(6)-(3)/(30)\\\\ & =\sf (25)/(30)-(3)/(30)\\\\ & =\sf (22)/(30)\\\\ & = \sf (11)/(15)\end{aligned}

Or, we can simply read P(contains apple or blueberry) from the Venn diagram.

P(A or B) is the total of the numbers inside the circles divided by the total number of smoothies:


\sf P(A\:or\:B) = (12+3+7)/(30)=(22)/(30)=(11)/(15)

Part (c)

For two events, A and B, where A and B are mutually exclusive:


\sf P(A \: or \: B)=P(A)+P(B)

Given:


\sf P(A)+P(B)=(5)/(6) \quad \textsf{(from part a)}


\sf P(A\:or\:B)=(11)/(15) \quad \textsf{(from part b)}


\sf As\:(11)/(15)\\eq (5)/(6) \implies P(A \: or \: B)\\eq P(A)+P(B)

Therefore, choosing a smoothie containing apple and choosing a smoothie containing blueberry are NOT mutually exclusive events.