The possible size of two sets intersection

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In a group of people $60\%$ peope like chocolate and $70\%$ like strawberry. What is the percentage of people who like both chocolate and strawberry?

I know this question is very basic I don't know what I should use here and I didn't find the solution write-up. What is the correct way to solve the above question?

I simply used the following method which is incorrect:

$$60\% = \frac{60}{100} = 0.6$$

$$70\% = \frac{70}{100} = 0.7$$

Number of people who like both = $0.7 - 0.6 = 0.1$

$$0.1 = 0.1 × 100 = 10\%$$

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There is not enough information to solve this problem uniquely. Consider a group of $10$ people labelled $1$ through $10$.

If $1$ through $6$ like chocolate and $1$ through $7$ like strawberry then the percentage of people who like both is $60\%$.

If $1$ through $6$ like chocolate and $4$ through $10$ like strawberry then the percentage of people who like both is $30\%$.

With similar games on larger populations I'm sure we could get every percentage inbetween as well.