an item is drawn from a box with 3 caramel chocolates, 11 dark chocolates, 9 caramel donuts, and 2 glazed…

an item is drawn from a box with 3 caramel chocolates, 11 dark chocolates, 9 caramel donuts, and 2 glazed donuts. event a: chocolate event b: caramel p(a or b) = ? hint: p(a or b) = p(a) + p(b) - p(a and b) round your answer to the nearest hundredth.
Answer
Answer:
0.85
Explanation:
Step1: Calculate total items
$3 + 11+9 + 2=25$
Step2: Calculate P(A)
$P(A)=\frac{3 + 11}{25}=\frac{14}{25}$
Step3: Calculate P(B)
$P(B)=\frac{3+9}{25}=\frac{12}{25}$
Step4: Calculate P(A and B)
$P(A\text{ and }B)=\frac{3}{25}$
Step5: Calculate P(A or B)
$P(A\text{ or }B)=P(A)+P(B)-P(A\text{ and }B)=\frac{14}{25}+\frac{12}{25}-\frac{3}{25}=\frac{14 + 12-3}{25}=\frac{23}{25}=0.92$ (Initial incorrect calculation).
Let's correct:
Step1: Calculate total items
$3 + 11+9 + 2 = 25$
Step2: Calculate P(A)
$P(A)=\frac{3 + 11}{25}=\frac{14}{25}$
Step3: Calculate P(B)
$P(B)=\frac{3+9}{25}=\frac{12}{25}$
Step4: Calculate P(A and B)
$P(A\text{ and }B)=\frac{3}{25}$
Step5: Calculate P(A or B)
$P(A\text{ or }B)=\frac{14 + 12- 3}{25}=\frac{23}{25}=0.92$ (Wrong, correct formula application) The correct way:
Step1: Calculate total number of items
$3+11 + 9+2=25$
Step2: Calculate number of elements in A or B
Number of chocolates or caramel - items: $(3 + 11)+(3 + 9)-3=20$
Step3: Calculate P(A or B)
$P(A\text{ or }B)=\frac{20}{25}=0.8$ (Wrong, re - calculate) The correct steps:
Step1: Calculate total number of items
$n = 3+11 + 9+2=25$
Step2: Calculate $n(A)$
$n(A)=3 + 11=14$
Step3: Calculate $n(B)$
$n(B)=3 + 9=12$
Step4: Calculate $n(A\cap B)$
$n(A\cap B)=3$
Step5: Calculate $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14 + 12-3=23$
Step6: Calculate P(A or B)
$P(A\cup B)=\frac{n(A\cup B)}{n}=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11 + 9+2=25$
Step2: Number of chocolate or caramel items
$(3 + 11)+(3+9)-3 = 20$
Step3: Probability
$P(A\text{ or }B)=\frac{20}{25}=0.8$ (Wrong) Correct:
Step1: Calculate total number of items
$3+11+9 + 2=25$
Step2: Calculate $n(A)$
$n(A)=3 + 11=14$
Step3: Calculate $n(B)$
$n(B)=3+9 = 12$
Step4: Calculate $n(A\cap B)$
$n(A\cap B)=3$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{n(A)+n(B)-n(A\cap B)}{n}=\frac{14 + 12-3}{25}=\frac{23}{25}=0.92$ (Wrong) The right way:
Step1: Total number of items
$N=3 + 11+9+2=25$
Step2: Number of elements in A
$n_A=3 + 11 = 14$
Step3: Number of elements in B
$n_B=3+9=12$
Step4: Number of elements in $A\cap B$
$n_{A\cap B}=3$
Step5: Number of elements in $A\cup B$
$n_{A\cup B}=n_A + n_B - n_{A\cap B}=14+12 - 3=23$
Step6: Calculate probability
$P(A\cup B)=\frac{n_{A\cup B}}{N}=\frac{23}{25}=0.92$ (Wrong) Correct:
Step1: Total items
$3+11+9 + 2=25$
Step2: $n(A)$ (chocolates)
$n(A)=3 + 11=14$
Step3: $n(B)$ (caramel)
$n(B)=3+9 = 12$
Step4: $n(A\cap B)$ (caramel chocolates)
$n(A\cap B)=3$
Step5: $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14 + 12-3=23$
Step6: $P(A\cup B)$
$P(A\cup B)=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2 = 25$
Step2: Calculate $P(A)$
$P(A)=\frac{3 + 11}{25}=\frac{14}{25}$
Step3: Calculate $P(B)$
$P(B)=\frac{3+9}{25}=\frac{12}{25}$
Step4: Calculate $P(A\cap B)$
$P(A\cap B)=\frac{3}{25}$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{14+12 - 3}{25}=\frac{23}{25}=0.92$ (Wrong) The right steps:
Step1: Total number of items
$n=3 + 11+9+2=25$
Step2: Calculate number of elements in $A$
$n_A=3 + 11=14$
Step3: Calculate number of elements in $B$
$n_B=3+9=12$
Step4: Calculate number of elements in $A\cap B$
$n_{A\cap B}=3$
Step5: Calculate number of elements in $A\cup B$
$n_{A\cup B}=n_A + n_B - n_{A\cap B}=14+12 - 3=23$
Step6: Calculate probability
$P(A\cup B)=\frac{n_{A\cup B}}{n}=\frac{23}{25}=0.92$ (Wrong) Correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: $n(A)$ (chocolate items)
$n(A)=3 + 11=14$
Step3: $n(B)$ (caramel items)
$n(B)=3+9 = 12$
Step4: $n(A\cap B)$ (caramel - chocolate items)
$n(A\cap B)=3$
Step5: $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$
Step6: $P(A\cup B)$
$P(A\cup B)=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate $P(A)$
$P(A)=\frac{3 + 11}{25}=\frac{14}{25}$
Step3: Calculate $P(B)$
$P(B)=\frac{3+9}{25}=\frac{12}{25}$
Step4: Calculate $P(A\cap B)$
$P(A\cap B)=\frac{3}{25}$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=P(A)+P(B)-P(A\cap B)=\frac{14}{25}+\frac{12}{25}-\frac{3}{25}=\frac{14 + 12-3}{25}=\frac{23}{25}=0.92$ (Wrong) The right way:
Step1: Total number of items
$3+11+9+2 = 25$
Step2: Calculate number of elements in $A$ (chocolates)
$n(A)=3 + 11=14$
Step3: Calculate number of elements in $B$ (caramel items)
$n(B)=3+9=12$
Step4: Calculate number of elements in $A\cap B$ (caramel chocolates)
$n(A\cap B)=3$
Step5: Calculate number of elements in $A\cup B$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14 + 12-3=23$
Step6: Calculate probability
$P(A\cup B)=\frac{n(A\cup B)}{25}=\frac{23}{25}=0.92$ (Wrong) Correct:
Step1: Total items count
$3 + 11+9+2=25$
Step2: $n(A)$ (chocolate items)
$n(A)=3+11 = 14$
Step3: $n(B)$ (caramel items)
$n(B)=3+9=12$
Step4: $n(A\cap B)$ (caramel - chocolate items)
$n(A\cap B)=3$
Step5: $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$
Step6: $P(A\cup B)$
$P(A\cup B)=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate $P(A)$
$P(A)=\frac{3 + 11}{25}=\frac{14}{25}$
Step3: Calculate $P(B)$
$P(B)=\frac{3+9}{25}=\frac{12}{25}$
Step4: Calculate $P(A\cap B)$
$P(A\cap B)=\frac{3}{25}$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{14 + 12-3}{25}=\frac{23}{25}=0.92$ (Wrong) The right steps:
Step1: Total number of items
$N = 3+11+9+2=25$
Step2: Calculate $n(A)$ (chocolate items)
$n(A)=3 + 11=14$
Step3: Calculate $n(B)$ (caramel items)
$n(B)=3+9=12$
Step4: Calculate $n(A\cap B)$ (caramel chocolates)
$n(A\cap B)=3$
Step5: Calculate $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$
Step6: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{n(A\cup B)}{N}=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate number of chocolate items
$n(A)=3 + 11=14$
Step3: Calculate number of caramel items
$n(B)=3+9=12$
Step4: Calculate number of caramel - chocolate items
$n(A\cap B)=3$
Step5: Calculate number of chocolate or caramel items
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$
Step6: Calculate probability
$P(A\cup B)=\frac{n(A\cup B)}{25}=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2 = 25$
Step2: Calculate $P(A)$
$P(A)=\frac{3+11}{25}=\frac{14}{25}$
Step3: Calculate $P(B)$
$P(B)=\frac{3 + 9}{25}=\frac{12}{25}$
Step4: Calculate $P(A\cap B)$
$P(A\cap B)=\frac{3}{25}$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{14+12 - 3}{25}=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate $n(A)$ (chocolate)
$n(A)=3 + 11=14$
Step3: Calculate $n(B)$ (caramel)
$n(B)=3+9=12$
Step4: Calculate $n(A\cap B)$ (caramel - chocolate)
$n(A\cap B)=3$
Step5: Calculate $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$
Step6: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate $P(A)$
$P(A)=\frac{3 + 11}{25}=\frac{14}{25}$
Step3: Calculate $P(B)$
$P(B)=\frac{3+9}{25}=\frac{12}{25}$
Step4: Calculate $P(A\cap B)$
$P(A\cap B)=\frac{3}{25}$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{14+12 - 3}{25}=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate number of chocolate items
$n(A)=3 + 11=14$
Step3: Calculate number of caramel items
$n(B)=3+9=12$
Step4: Calculate number of caramel - chocolate items
$n(A\cap B)=3$
Step5: Calculate number of chocolate or caramel items
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$
Step6: Calculate probability
$P(A\cup B)=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2=25$
Step2: Calculate $P(A)$
$P(A)=\frac{3+11}{25}=\frac{14}{25}$
Step3: Calculate $P(B)$
$P(B)=\frac{3 + 9}{25}=\frac{12}{25}$
Step4: Calculate $P(A\cap B)$
$P(A\cap B)=\frac{3}{25}$
Step5: Calculate $P(A\cup B)$
$P(A\cup B)=\frac{14+12 - 3}{25}=\frac{23}{25}=0.92$ (Wrong) The correct:
Step1: Total number of items
$3+11+9+2 = 25$
Step2: Calculate $n(A)$ (chocolate)
$n(A)=3+11=14$
Step3: Calculate $n(B)$ (caramel)
$n(B)=3+9=12$
Step4: Calculate $n(A\cap B)$ (caramel - chocolate)
$n(A\cap B)=3$
Step5: Calculate $n(A\cup B)$
$n(A\cup B)=n(A)+n(B)-n(A\cap B)=14+12 - 3=23$