Theory
Exercises
1. 
Choose the correct answer
Difficulty: easy 
3

2. 
Find the solution
Difficulty: easy 
2

3. 
Determine the value
Difficulty: easy 
2

4. 
Estimate the value of 'x' and 'y'
Difficulty: medium 
2

5. 
Find the two numbers
Difficulty: medium 
2

6. 
Find the number of tickets
Difficulty: medium 
2

7. 
Determine the cost
Difficulty: hard 
4

8. 
Estimate the age
Difficulty: hard 
4

9. 
Evaluate the cost
Difficulty: hard 
4

Tests
1. 
Training test
Difficulty: easy 
9

2. 
Training test
Difficulty: medium 
6
