Numerical Ability
Percentages, Ratio, Word Problems & Number Series (30% of exam)
Essential Formulas
Percentage
Percentage = (Part / Whole) × 100
Part = (Percentage × Whole) / 100
Whole = (Part × 100) / Percentage
Ratio & Proportion
a : b = c : d means a/b = c/d
Cross multiply: a × d = b × c
Distance, Speed, Time
Distance = Speed × Time
Speed = Distance / Time
Time = Distance / Speed
Simple Interest
I = P × R × T
P = Principal, R = Rate (decimal), T = Time
Discount & Markup
Discount = Original Price × Rate
Sale Price = Original - Discount
Average
Average = Sum of all values / Count
Sum = Average × Count
Number Series Patterns
Arithmetic Sequence (Add/Subtract constant)
2, 5, 8, 11, 14, 17 (adding 3)
Geometric Sequence (Multiply/Divide constant)
2, 6, 18, 54, 162 (multiply by 3)
Fibonacci-like (Add previous two)
1, 1, 2, 3, 5, 8, 13
Alternating Patterns
2, 5, 4, 7, 6, 9, 8 (two sequences: 2,4,6,8 and 5,7,9)
Square Numbers
1, 4, 9, 16, 25, 36 (1², 2², 3², 4², 5², 6²)
Increasing Difference
2, 3, 5, 8, 12, 17 (differences: +1, +2, +3, +4, +5)
Word Problem Examples
Percentage Problem
A shirt originally costs ₱500. It is on sale at 20% off. What is the sale price?
Discount = ₱500 × 0.20 = ₱100
Sale Price = ₱500 - ₱100 = ₱400
Ratio Problem
If 3 pencils cost ₱15, how much do 7 pencils cost?
3 : 15 = 7 : x
3x = 15 × 7 = 105
x = 105 / 3 = ₱35
Distance Problem
A car travels 120 km in 2 hours. What is its speed?
Speed = Distance / Time = 120 / 2 = 60 km/hr
Age Problem
Maria is twice as old as Juan. In 5 years, Maria will be 25. How old is Juan now?
Maria now = 25 - 5 = 20 years
Juan = 20 / 2 = 10 years old
Problem-Solving Strategy
- 1Read carefully - Identify what's being asked
- 2List the given - Write down all numbers and relationships
- 3Choose the formula - Match the problem type to the appropriate formula
- 4Solve step by step - Show your work and check each step
- 5Check your answer - Does it make sense? Plug it back in.