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Excel in math and science
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Rule of Sum and Rule of Product
Seek simple and succinct solutions in these systems by sussing-out the significant symmetries.
Excel in math and science
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It's hard to learn from lectures and videos
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Our wiki is made for math and science
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How many integers \(n\) satisfy the inequality \( 22 \leq n \leq 49\)?
Excel in math and science
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Our wiki is made for math and science
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by Brilliant Staff
How many integers are greater than or equal to \( 986\) but strictly less than \(1031?\)
Excel in math and science
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by Brilliant Staff
How many integers \(n\) are there satisfying the inequality \[479 < n < 559?\]
Excel in math and science
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How many positive 2 digit numbers are there, such that the units digit is strictly smaller than the tens digit?
Details and assumptions
The number \(12=012\) is a 2-digit number, not a 3-digit number.
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
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Han Dynasty is the second imperial dynasty of China. It was established in 206 BCE and survived until 220 CE. How many years are there between its establishment and collapse inclusive of both ends?
Excel in math and science
Master concepts by solving fun, challenging problems.
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Our wiki is made for math and science
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by Brilliant Staff