Question:
A survey of 300 people found that 180 like coffee, 120 like tea, and 90 like both. How many people like only coffee?
A survey of 300 people found that 180 like coffee, 120 like tea, and 90 like both. How many people like only coffee?
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To find the number of people who like only one option, subtract the number who like both from the total who like that option.
Updated On: Oct 4, 2025
- 60
- 90
- 120
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The Correct Option is B
Solution and Explanation
Using the principle of inclusion and exclusion:
[6pt] Let: - \( 180 \) be the total number of people who drink coffee or tea. - \( 90 \) be the number of people who drink both coffee and tea. The number of people who drink only coffee can be found by subtracting the number of people who drink both from the total number of coffee drinkers: \[ \text{Only coffee} = 180 - 90 = 90. \]
[6pt] Let: - \( 180 \) be the total number of people who drink coffee or tea. - \( 90 \) be the number of people who drink both coffee and tea. The number of people who drink only coffee can be found by subtracting the number of people who drink both from the total number of coffee drinkers: \[ \text{Only coffee} = 180 - 90 = 90. \]
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