2008_Solutions_Grades 7-8-2008_Solutions_Levels

2008_Solutions_Levels_7&8
Pdf Summary
The document provides suggested solutions for the Math Kangaroo 2008 competition for levels 7 and 8, covering a range of mathematical problems and concepts. Each solution outlines steps and logical reasoning used to reach the corresponding answer for each numbered question.<br /><br />1. The comparison of expressions uses arithmetic concepts, leading to choice B.<br />2. C is chosen by calculating the number of girls with a cold from given totals.<br />3. Substitution in mathematical expressions results in answer B.<br />4. Calculation of circular motion timing deduces answer C.<br />5. Trial and error in numerical arrangement results in answer C.<br />6. Basic arithmetic is used to determine sum sequences, leading to E.<br />7. Geometrical reasoning on perimeters guides to answer B.<br />8. Finds the highest common divisor resulting in E.<br />9. Surface area addition results in answer E.<br />10. Angle calculations in a geometric figure lead to answer A.<br />11. Analysis of geometric arrangements confirms answer C.<br />12. Coin distribution is calculated to achieve equality, resulting in B.<br />13. Predicting digit occurrences in years to find when a specific condition happens again gives answer A.<br />14. Number pairs and their relationships clarify answer C.<br />15. Trial and error with numbers within provided ranges concludes with A.<br />16. Solving angles within triangles results in A.<br />17. Solving a system of equations that represents perimeter problems confirms C.<br />18. Length and distance calculations between points give A.<br />19. Using area formulas and geometric shapes yields D.<br />20. Examination of net shapes determining possible cubes leads to D.<br />21. Analysis of unit cube visibility gives D.<br />22. Factorial-like operations and properties give C.<br />23. Angle relationships and properties within triangles provide C.<br />24. Maximizing number values under constraints leads to answer D.<br />25. Testing conditions in fractions results in C.<br />26. Logical deduction from statements about honesty confirms A.<br />27. Proportions in motion problems lead to B.<br />28. Set and permutation properties confirm D.<br />29. Geometry and angle relationships determine C.<br />30. Logical deduction on number parities results in B.<br /><br />These solutions involve various math skills like arithmetic, geometry, logic, algebra, and problem-solving techniques.
Keywords
Math Kangaroo 2008
mathematical problems
solution steps
arithmetic concepts
geometrical reasoning
logical deduction
problem-solving
algebra
geometry
permutations