1. Alex buys a sandwich for 8.50 dollars and a drink for 2.25 dollars. He pays with a 20 dollar bill. How much change, in dollars, does he receive? ___
2. On Saturday, Maria walked her dog 3.8 km. On Sunday, she walked 1.5 km farther than on Saturday. What was the total distance she walked over the weekend?
3. A recipe requires 0.75 liters of milk. David has a 2-liter carton. If he makes a double batch of the recipe, how many liters of milk will be left? ___
4. A video game character has 85.5 health points. They lose 15.2 points in a battle, then use a potion that restores 25.0 points. What is their final health? ___
5. An empty bucket weighs 1.2 kg. A worker adds 8.5 kg of sand to it. Then, 3.25 kg of sand is poured out. What is the final weight of the bucket with the remaining sand, in kg? ___
6. Calculate the sum: $162.45 + 83.7 = \_\_\_$
7. Calculate the difference: $310.6 - 58.241 = \_\_\_$
8. What is the sum of $47.82$ and $5.9$?
9. When adding or subtracting decimals, what is the most important first step?
10. A ribbon was $150.5$ cm long. After a piece measuring $85.12$ cm was cut off, what is the length of the remaining ribbon? The remaining length is ___ cm.