In class, 30% of the students offered mathematics 20% offered chemistr

1.	In class, 30% of the students offered mathematics 20% offered chemistry and 10% offered both. If a student is selected at random, find the probability that he has offered mathematics or chemistry.
Answer» Given: Math students = 30% Chemistry Students = 20% Math & Chemistry both = 10% To Find: P(Math or Chemistry) Now, P(Math) = 30% = \(\frac{30}{100}\) = 0.30 P(Chemistry) 30% = \(\frac{20}{100}\) = 0.20 P(Math ∩ Chemistry) = 10% = \(\frac{10}{100}\) = 0.10 We know that, P(A ∪ B) = P(A) + P(B) – P(A ∩ B) Therefore, P(Math ∪ Chemistry) = 0.30 + 0.20 – 0.10 = 0.40 Hence, number of students studying math or chemistry are 40%.

In class, 30% of the students offered mathematics 20% offered chemistry and 10% offered both. If a student is selected at random, find the probability that he has offered mathematics or chemistry.

Answer»

Given: Math students = 30%

Chemistry Students = 20%

Math & Chemistry both = 10%

To Find: P(Math or Chemistry)

Now, P(Math) = 30% = \(\frac{30}{100}\) = 0.30

P(Chemistry) 30% = \(\frac{20}{100}\) = 0.20

P(Math ∩ Chemistry) = 10% = \(\frac{10}{100}\) = 0.10

We know that,

P(A ∪ B) = P(A) + P(B) – P(A ∩ B)

Therefore,

P(Math ∪ Chemistry) = 0.30 + 0.20 – 0.10 = 0.40

Hence, number of students studying math or chemistry are 40%.

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In class, 30% of the students offered mathematics 20% offered chemistry and 10% offered both. If a student is selected at random, find the probability that he has offered mathematics or chemistry.

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