Section 1: Numbers (Arithmetic, Percentages, Ratios, Fractions)

1. Calculate 20 percent of 450 and explain each step used to arrive at the answer.
2. A product costs 800. It is increased by 15 percent. Find the new price and describe how percentage increase works.
3. A salary of 1200 is reduced by 10 percent. Calculate the new salary and explain the reduction process.
4. The price of an item increases from 500 to 650. Calculate the percentage increase and interpret the result.
5. The ratio of boys to girls in a class is 3:2, and the total number of students is 50. Determine how many boys and girls are in the class.
6. Simplify the ratio 20:30 to its lowest terms and explain the method used.
7. Convert the fraction 3/4 into a percentage and explain the conversion process.
8. Add the fractions 2/3 and 1/6, showing how to find a common denominator.
9. Multiply the fractions 5/8 and 4/5 and simplify the result.
10. Divide the fraction 7/9 by 2/3 and explain the rule used for division of fractions.

Section 2: Algebra Basics (Variables and Equations)

1. Solve the equation x + 5 = 12 and explain how isolating the variable works.
2. Solve the equation 2x = 18 and describe the steps involved.
3. Solve the equation 3x + 4 = 19 and explain how to handle multiple operations.
4. Solve the equation 5x − 10 = 0 and interpret the result.
5. If x = 4, evaluate the expression 2x² + 3x and explain substitution.
6. Solve the equation x/2 = 7 and describe how division equations are handled.
7. Solve the equation 4x + 2 = 2x + 10 and explain how to bring variables to one side.