Practice china-kaoyan-math-3 questions with answers and explanations.
An antiderivative is 4/2 x²+4x. At x=5, the value is 70.0.
The dot product is 4×2+5×4=28.
Rewrite the value using base 5: 3125 = 5^5. Matching exponents gives x = 5.
Choose an option to check your answer.
Use the circle-area formula A = πr². Substituting r = 9 gives A = π × 9² = 81π.
Percentage=(8/23)×100=34.78.
Subtract 4 from both sides and divide by 3: x = (34-4)/3 = 10.
By Vieta’s formula, the sum of the roots equals the coefficient 7.
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The sum is n(n+1)/2=10, so the mean is 10/4.
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There are 5 favourable outcomes out of 11 equally likely outcomes, so P(red)=5/11.
Rewrite the value using base 4: 256 = 4^4. Matching exponents gives x = 4.
Choose an option to check your answer.
Use the circle-area formula A = πr². Substituting r = 8 gives A = π × 8² = 64π.
Percentage=(7/22)×100=31.82.
