Probability

Hi guys! Some people in our class are wondering if conditional probability can be used in this problem. Can you please give clarification to the problem? Thank you!

In a senior year of a high school graduating class of 100 students, 42 studied mathematics, 68 studied psychology, 54 studied history, 21 studied both mathematics and history, 25 studied mathematics and psychology, 7 studied history but neither mathematics nor psychology, 10 studied all the subjects, and 8 did not take any of the three. If a student is selected at random, find the probability that.....

a person is not taking psychology is taking both history and mathematics.

Easy Math Editor

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`2 \times 3`	$2 \times 3$
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Comments

No conditional probability needed. Just draw a Venn diagram and the answer should follow.

Pi Han Goh - 4 years, 3 months ago

Sorry for replying late. Thank you! Even my teacher believed that conditional probability is applied. I needed some proof to prove otherwise.

Charlene Lim - 3 years, 5 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$