Practice China questions with answers and explanations.
Rewrite the value using base 4: 256 = 4^4. Matching exponents gives x = 4.
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Use the circle-area formula A = πr². Substituting r = 4 gives A = π × 4² = 16π.
Percentage=(11/46)×100=23.91.
Subtract 3 from both sides and divide by 8: x = (51-3)/8 = 6.
By Vieta’s formula, the sum of the roots equals the coefficient 8.
aₙ=a₁+(n−1)d=2+(8−1)×4=30.
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The sum is n(n+1)/2=45, so the mean is 45/9.
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There are 3 favourable outcomes out of 8 equally likely outcomes, so P(red)=3/8.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
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Use the circle-area formula A = πr². Substituting r = 3 gives A = π × 3² = 9π.
Percentage=(10/45)×100=22.22.
Subtract 11 from both sides and divide by 7: x = (46-11)/7 = 5.
