Question

Could anyone help me decipher this alien language????​

Answer 1

Answer:

OPTION A: $\frac{11}{20}$

Step-by-step explanation:

$P(A | B) = \frac{P(A \cap B)}{P(B)}$

$P(not B) = 1 - P(B) = 1 - \frac{13}{20} = \frac{7}{20}$

$\implies P(A \cap B)= P(A | B) \times P(B)$

$= \frac{11}{20} \times \frac{7}{20}$

Let us keep it without multiplying for easy simplification later.

Also, let us assume A and B are independent events.

$P(A \cap B) = P(A) \times P(B)$

$\implies \frac{11}{20} \times \frac{7}{20} = P(A) \times \frac{7}{20}$

$\implies P(A) = \frac{11}{20}$

Hence, OPTION A 11/20 is the answer.