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Excel in math and science
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Basic Mathematics
Reasoning Skills
Excel in math and science
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Which of the following is closest to
\[ 123,456,789 \times 987,654,321 ? \]
(A) \(\ \ 1.0 \times 10^{15}\)
(B) \(\ \ 1.0 \times 10^{16}\)
(C) \(\ \ 1.0 \times 10^{17}\)
(D) \(\ \ 1.0 \times 10^{18}\)
(E) \(\ \ 1.0 \times 10^{19}\)
Excel in math and science
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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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by Brilliant Staff
If Kevin has \(25\) quarters, \(3\) dimes, \(5\) nickels, and \(2\) pennies in his pocket, approximately how much money does he have?
(A) \(\ \ $2.5\)
(B) \(\ \ $6.25\)
(C) \(\ \ $6.8\)
(D) \(\ \ $25.35\)
(E) \(\ \ $680\)
NOTE: One quarter is \($0.25,\) one dime is \($0.1,\) one nickel is \($0.05,\) and one penny is \($0.01.\)
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
Master advanced concepts through explanations,
examples, and problems from the community.
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by Brilliant Staff
If Jane gets \(99\)% on her math test, Tom gets \(89\)% and James gets \(71\)%, what is their approximate average score?
(A) \(\ \ 77\)%
(B) \(\ \ 80\)%
(C) \(\ \ 86\)%
(D) \(\ \ 89\)%
(E) \(\ \ 94\)%
Excel in math and science
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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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by Brilliant Staff
(A) \(\ \ 9:4\)
(B) \(\ \ 4:9\)
(C) \(\ \ 3:2\)
(D) \(\ \ 2:3\)
(E) \(\ \ 1:1\)
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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by Brilliant Staff
What is the best approximation of \(\sqrt{96}+\sqrt{124}?\)
(A) \(\ \ 19\)
(B) \(\ \ 20\)
(C) \(\ \ 21\)
(D) \(\ \ 22\)
(E) \(\ \ 23\)
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
Master advanced concepts through explanations,
examples, and problems from the community.
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including olympiad champions, researchers, and professionals.
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by Brilliant Staff