Quantitative Reasoning
"Tol! Math sa Police Exam? Yes, kailangan mo mag-compute ng distance, time, crime rate, at marami pang stats! Numbers ang katotohanan sa law enforcement!"
1. Basic Arithmetic Operations โโโ๏ธโ
Foundation ng lahat ng math problems. Dapat mabilis at accurate!
Order of Operations (PEMDAS/BODMAS):
Parentheses / Brackets - First
Exponents / Orders - Second
Multiplication & Division - Left to right
Addition & Subtraction - Left to right
Example:
5 + 3 ร 2 = ?
โ Wrong: 16 (adding first)
โ Correct: 11 (multiply first)
2. Fractions, Decimals & Percentages ๐
Conversion between these is crucial for police statistics!
Fraction
1/4
Decimal
0.25
Percentage
25%
๐ Conversion Formulas:
- โข Fraction โ Decimal: Divide numerator by denominator
- โข Decimal โ Percentage: Multiply by 100
- โข Percentage โ Decimal: Divide by 100
- โข Percentage โ Fraction: Put over 100, simplify
๐ Percentage Problems:
Finding Percentage:
What is 15% of 200? โ 0.15 ร 200 = 30
Finding the Whole:
30 is 15% of what? โ 30 รท 0.15 = 200
Finding the Rate:
30 is what percent of 200? โ (30 รท 200) ร 100 = 15%
3. Distance, Speed, Time: The Police Triangle ๐
Tol, pursuit situations require quick calculations!
The DST Triangle
D
Distance
D = S ร T
S
Speed
S = D รท T
T
Time
T = D รท S
๐ Police Scenario Examples:
Example 1:
A patrol car travels 120 km in 2 hours. What is the average speed?
S = D รท T = 120 รท 2 = 60 km/h
Example 2:
A suspect is running at 15 km/h. How far will he go in 20 minutes?
D = S ร T = 15 ร (20/60) = 15 ร 0.33 = 5 km
Example 3:
Reinforcement is 30 km away, traveling at 60 km/h. ETA?
T = D รท S = 30 รท 60 = 0.5 hours = 30 minutes
4. Ratio and Proportion ๐
Para sa resource allocation, manpower distribution, at statistics!
Ratio:
Comparison of two quantities
Example: Police-to-population ratio
50 police : 10,000 people = 1:200
Proportion:
Equality of two ratios
a/b = c/d
Cross multiply: a ร d = b ร c
๐ฏ Practice Problem:
If 3 police officers can patrol 12 blocks, how many officers are needed for 28 blocks?
Solution
3/12 = x/28
12x = 3 ร 28
12x = 84
x = 84 รท 12 = 7 officers
5. Crime Statistics & Data Interpretation ๐
Tol, numbers tell the story of crime trends!
Key Statistical Measures:
Mean (Average)
Sum of all values รท Number of values
Example: Average crimes per month
Median
Middle value when arranged in order
Example: Middle age of offenders
Mode
Most frequently occurring value
Example: Most common crime type
Range
Highest value - Lowest value
Example: Spread of response times
๐ Crime Rate Formula:
Crime Rate = (Number of Crimes รท Population) ร 100,000
Example:
500 crimes in a city of 250,000 people
Rate = (500 รท 250,000) ร 100,000 = 200 per 100,000
6. Work & Time Problems โฐ
Para sa task completion at resource planning!
Work Rate Formula:
Work = Rate ร Time
Rate = 1/Time to complete the job
Example:
Officer A can complete a report in 3 hours.
Officer B can complete it in 6 hours.
How long if they work together?
Rate A = 1/3, Rate B = 1/6
Combined Rate = 1/3 + 1/6 = 2/6 + 1/6 = 3/6 = 1/2
Time = 1 รท (1/2) = 2 hours
7. Age Problems ๐ค
Classic sa exams - mga computation ng edad!
๐ฏ Age Problem Tips:
- โข Let x = present age (usually)
- โข "Years ago" means subtract
- โข "Years from now" means add
- โข Set up equation based on relationship
Example:
Juan is 3 times as old as Pedro. In 10 years, Juan will be twice as old.
How old is Pedro now?
Solution
Let Pedro's age = x, Juan's age = 3x
In 10 years: 3x + 10 = 2(x + 10)
3x + 10 = 2x + 20
x = 10
Pedro is 10 years old
๐ฏ Quantitative Reasoning Exam Strategy
Tips for Success, Tol:
๐ During the Exam:
- โข Read the problem twice
- โข Identify what's being asked
- โข Write down given information
- โข Show your work (for checking)
โก Time-Saving Tips:
- โข Estimate before computing
- โข Use elimination method
- โข Skip hard ones, return later
- โข Double-check calculations
Numbers don't lie, Tol! Master the math, master the exam! ๐ข๐ช
Test Your Knowledge! ๐ง
Ready ka na ba? Take the practice quiz for Quantitative Reasoning to reinforce what you just learned.
Start Practice Quiz ๐