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junior college 2 | H2 Maths
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Sophie
Sophie

junior college 2 chevron_right H2 Maths

Hi! What is the difference between 21C2 and 21C1x20C1? I thought they both meant 2 different choice will be pick out from total 21, but their answer is not the same..

Date Posted: 6 years ago
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Tham KY
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Sophie
Sophie
6 years ago
thank you!