Challenging Questions( Week 50 Evaluation) 1. There are a total of 30 motorcycles (2-wheel) and cars (4-wheel) in a parking lot. Together, there are 84 wheels. How many motorcycles and cars are there respectively?(Only write down the numbers separated by a comma.) 2. There are a certain number of ducks and rabbits, which have 21 heads and 60 legs all together. How many ducks and rabbits are there respectively? (Only write down the numbers separated by a comma). 3. Draw a polygon with 6 sides. How many diagonals can you draw inside the polygon? 4. 2n is n 2s multiplied together. 22 = 2 × 2 = 4 and its last digit is 4, 24 = 2 × 2 × 2 × 2 = 16 and its last digit is 6. What is the last digit of 214? 5. The average of 8 numbers is 11. Suppose 29 is added the group. What is the new average of all the numbers? 6. In the morning, it takes Anne 2 minutes to brush her teeth, 2 minutes to put on makeup, 5 minutes to boil water for tea, and 2 minutes to wait the tea to cool down. After these chores, she needs 4 minutes to finish her breakfast. What is the least amount of time (in minutes) she will need to finish all of the above if she organizes her tasks reasonably? 7. Josh had 57 Yu-Gi-Oh cards, and Mary had none. Josh can move exactly 7 cards to Mary at a time, and Mary can move exactly 3 cards to Josh at a time. At least how many moves are needed to move all Josh's cards to Mary? 8. All the students in the class need to take at least one course in math and English in this semester. There are 27 students in the class. There are 11 students registered for math and 23 students registered for English. How many students are registered for both Math and English ? 10. The tickets for a concert cost $30 each. However, children can get a 20% discount. A group of 25 people consisting of children and adults paid a total of $720 for the concert. How many children were there in the group? |