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Lesson 2

Mathematics

1. Arithmetic Operations

Master the fundamental operations and order of operations (PEMDAS/GEMDAS).

Order of Operations (PEMDAS)

  1. Parentheses (or Grouping symbols)
  2. Exponents (powers and roots)
  3. Multiplication and Division (left to right)
  4. Addition and Subtraction (left to right)

Example

Solve: 3 + 4 × 2² - (6 ÷ 2)

  1. Parentheses: (6 ÷ 2) = 3
  2. Exponents: 2² = 4
  3. Multiplication: 4 × 4 = 16
  4. Addition/Subtraction: 3 + 16 - 3 = 16

2. Fractions & Decimals

Fractions

  • Addition/Subtraction: Find LCD first
  • Multiplication: Multiply numerators and denominators
  • Division: Flip the divisor and multiply
  • Simplifying: Divide by GCF

Decimals

  • Addition/Subtraction: Align decimal points
  • Multiplication: Count total decimal places
  • Division: Move decimal to make divisor whole
  • Conversion: Divide numerator by denominator

Common Fraction-Decimal-Percent Equivalents

1/2 = 0.5 = 50%
1/4 = 0.25 = 25%
3/4 = 0.75 = 75%
1/3 ≈ 0.33 = 33.33%
2/3 ≈ 0.67 = 66.67%
1/5 = 0.2 = 20%

3. Algebra

Algebra involves solving equations and working with variables.

Solving Linear Equations

  1. Simplify both sides (distribute, combine like terms)
  2. Move variables to one side (add/subtract)
  3. Move constants to the other side
  4. Divide by the coefficient

Example: Solve 3x + 5 = 2x + 12

3x - 2x = 12 - 5

x = 7

Factoring

  • • Common factor: ax + ay = a(x + y)
  • • Difference of squares: a² - b² = (a+b)(a-b)
  • • Trinomial: x² + 5x + 6 = (x+2)(x+3)

Quadratic Formula

For ax² + bx + c = 0:

x = (-b ± √(b²-4ac)) / 2a

4. Geometry

Essential formulas for area, perimeter, and volume.

2D Shapes

Rectangle

Area = l × w

Perimeter = 2(l + w)

Triangle

Area = ½ × b × h

Perimeter = a + b + c

Circle

Area = πr²

Circumference = 2πr

Trapezoid

Area = ½(b₁ + b₂) × h

3D Shapes

Rectangular Prism

Volume = l × w × h

Surface Area = 2(lw + lh + wh)

Cylinder

Volume = πr²h

Surface Area = 2πr² + 2πrh

Sphere

Volume = (4/3)πr³

Surface Area = 4πr²

Cone

Volume = (1/3)πr²h

Pythagorean Theorem

For right triangles: a² + b² = c²

Where c is the hypotenuse (longest side)

5. Statistics

Measures of central tendency and data analysis.

Measures of Central Tendency

  • Mean (Average): Sum of all values ÷ Number of values

    Example: {2, 4, 6, 8, 10} → Mean = 30/5 = 6

  • Median: Middle value when arranged in order

    For even count, average the two middle values

  • Mode: Most frequently occurring value

    A set can have no mode, one mode, or multiple modes

Other Measures

  • Range: Highest value - Lowest value
  • Weighted Average: Σ(value × weight) ÷ Σweights
  • Probability: Favorable outcomes ÷ Total possible outcomes

6. Word Problems

Strategies for solving mathematical word problems.

Problem-Solving Steps

  1. Read the problem carefully (identify what is being asked)
  2. Identify the given information
  3. Determine what operation(s) to use
  4. Set up the equation
  5. Solve and check your answer

Common Types

  • Age Problems: Use variables for ages, set up equations
  • Distance Problems: Distance = Rate × Time
  • Work Problems: Combined rate = 1/time₁ + 1/time₂
  • Percentage Problems: Part = Whole × Percentage
  • Ratio Problems: Set up proportions

Example: Age Problem

Maria is 5 years older than Juan. In 3 years, their ages will total 35. How old is Juan now?

Let x = Juan's age now

Maria's age = x + 5

In 3 years: (x + 3) + (x + 5 + 3) = 35

2x + 11 = 35 → x = 12

Juan is 12 years old.

PUPCET Math Tips

  • Memorize formulas - know area, perimeter, and volume formulas.
  • Practice mental math - multiplication tables, squares, and cubes.
  • Show your work - avoid careless errors by writing out steps.
  • Check your answers - substitute back to verify.