Solved Exercises on Workplace Math in Grade 2

Master workplace math concepts: counting hours, calculating pay, solving work-related word problems through these 5 detailed exercises.

Solution: Exercises 1 to 3
1 Hours Worked
Exercise 1
Tom works from 9 AM to 3 PM. How many hours did he work?
Definition:

Hours worked: The time between starting and ending work

Time calculation method:
  1. Identify start and end times
  2. Subtract start time from end time
  3. Calculate the difference
Start Time
9 AM
End Time
3 PM
Hours Worked
3 PM - 9 AM = 6 hours
Step 1: Identify start time

Tom started working at 9 AM

Step 2: Identify end time

Tom finished working at 3 PM

Step 3: Calculate the difference

From 9 AM to 3 PM = 6 hours

Tom worked 6 hours
Final answer:

Tom worked 6 hours

Applied rules:

• Time calculation: End time - Start time = Hours worked

• Same day: Calculate within same 12-hour period

• Duration: Measure time span

2 Hourly Pay
Exercise 2
Sarah earns $5 per hour. She worked 4 hours today. How much money did she earn?
Definition:

Hourly pay: Money earned for each hour worked

Hourly Rate
$5/hour
Hours Worked
4 hours
Total Pay
$5 × 4 = $20
Step 1: Identify hourly rate

Sarah earns $5 for each hour

Step 2: Identify hours worked

Sarah worked 4 hours

Step 3: Calculate total pay

$5 per hour × 4 hours = $20

Sarah earned $20
Final answer:

Sarah earned $20

Applied rules:

• Multiplication: Hourly rate × Hours worked = Total pay

• Rate calculation: Amount per unit of time

• Pay formula: Rate × Time = Payment

3 Daily Schedule
Exercise 3
Mike starts work at 8 AM and takes a 1-hour lunch break. He works for 8 hours total. What time does he finish?
Definition:

Total work time: Actual working hours excluding breaks

Start Time
8 AM
Work Hours
8 hours
Break Time
1 hour
Finish Time
8 AM + 8 hours + 1 hour = 5 PM
Step 1: Identify start time

Mike starts at 8 AM

Step 2: Identify work hours

Mike works 8 hours

Step 3: Account for break time

Mike takes 1-hour lunch break

Step 4: Calculate finish time

8 AM + 8 hours of work + 1 hour break = 5 PM

Mike finishes at 5 PM
Final answer:

Mike finishes work at 5 PM

Applied rules:

• Time addition: Start time + Work time + Break time = Finish time

• Break inclusion: Break time adds to total duration

• Schedule planning: Consider all time segments

Workplace Math Facts
Total Pay = Hourly Rate × Hours Worked
Pay Calculation Formula
Workplace Math
Pay = Rate × Time
Hours Worked = End - Start
Time Facts
1 hour = 60 minutes
1 day = 24 hours
Money Facts
$1.00 = 100¢
Quarter = 25¢
Key definitions:

Hourly rate: Money earned per hour of work

Hours worked: Time spent doing work

Total pay: Total money earned

Complete methodology:
  1. Read the problem: Identify what's given and what's needed
  2. Identify variables: Find rates, times, and amounts
  3. Choose operation: Multiplication for pay, subtraction for time
  4. Calculate: Perform the math operation
  5. Check: Make sure answer makes sense
Tip 1: Remember: Pay = Rate × Time, always multiply rate by time.
Tip 2: Always subtract start time from end time to find duration.
Tip 3: Include breaks when calculating finish time.
Tip 4: Practice with real-world scenarios like job schedules.
Common errors: Forgetting to include breaks in schedule, mixing up multiplication and addition for pay calculations.
Practice tips: Use real job examples, practice with clocks, simulate work schedules.
Formulas to know by heart:

• Total Pay = Hourly Rate × Hours Worked

• Hours Worked = End Time - Start Time

• Change = Amount Paid - Cost

• $1.00 = 100¢

• Quarter = 25¢, Dime = 10¢, Nickel = 5¢, Penny = 1¢

Solution: Exercises 4 to 5
4 Multiple Days
Exercise 4
Anna works 6 hours per day for 5 days. She earns $4 per hour. How much does she earn in total?
Definition:

Weekly pay: Total money earned over multiple days

Daily Hours
6 hours/day
Days Worked
5 days
Total Hours
6 × 5 = 30 hours
Total Pay
$4 × 30 = $120
Step 1: Calculate total hours worked

6 hours per day × 5 days = 30 hours

Step 2: Calculate total pay

$4 per hour × 30 hours = $120

Step 3: State the final amount

Anna earns $120 in total

Anna earns $120
Final answer:

Anna earns $120 in total

Applied rules:

• Multiplication: Daily hours × Days = Total hours

• Pay calculation: Hourly rate × Total hours = Total pay

• Multi-step problems: Solve one part at a time

5 Work Schedule
Exercise 5
David works Monday to Friday. He starts at 9 AM and finishes at 5 PM with a 1-hour lunch break. How many hours does he work each week?
Definition:

Weekly hours: Total hours worked in a week

Daily Schedule
9 AM to 5 PM
Break Time
1 hour
Daily Work Hours
8 hours - 1 hour = 7 hours
Weekly Hours
7 hours × 5 days = 35 hours
Step 1: Calculate daily total time

From 9 AM to 5 PM = 8 hours

Step 2: Subtract break time

8 hours - 1 hour break = 7 hours of actual work

Step 3: Calculate weekly hours

7 hours per day × 5 days = 35 hours per week

Step 4: State the weekly total

David works 35 hours per week

David works 35 hours/week
Final answer:

David works 35 hours per week

Applied rules:

• Daily calculation: Total time - Break time = Work time

• Weekly calculation: Daily hours × Days per week

• Time management: Distinguish between presence and actual work

Detailed Summary: Workplace Math
Complete Learning Summary
Key Concepts & Definitions

Hourly rate: Money earned per hour of work

Hours worked: Time spent doing work

Total pay: Total money earned

Work schedule: Planned times for starting and ending work

Break time: Rest periods not counted as work time

Core Rules & Principles

• Pay Formula: Total Pay = Hourly Rate × Hours Worked

• Time Calculation: Hours Worked = End Time - Start Time

• Break Adjustment: Actual Work Time = Total Time - Break Time

• Multiplication: Rate × Time = Payment

• Money Conversion: $1.00 = 100¢

Step-by-Step Method

1. Identify: Find the given information (rate, time, hours)

2. Plan: Decide which formula to use

3. Calculate: Perform the necessary math operations

4. Adjust: Account for breaks or multiple days

5. Verify: Check that your answer makes sense

Examples & Applications

Simple Example: $5/hour × 3 hours = $15 earned

Medium Example: 9 AM to 3 PM = 6 hours worked

Complex Example: 7 hours/day × 5 days = 35 hours/week

Real World: Calculating paychecks, planning work schedules

Tips & Tricks

• Remember: Pay = Rate × Time, always multiply

• Watch Breaks: Don't count break time as work time

• Estimate First: Get a rough idea before calculating

• Check Your Work: Always verify your answer makes sense

• Practice Regularly: Use real scenarios to build skills

Memory Aids

• Pay Rhyme: "Rate times time gives pay, that's the way to calculate pay!"

• Time Rhyme: "End minus start gives hours, that's how time works!"

• Visual: Think of a job where you earn money for time worked

• Memory Trick: "RT = P" (Rate × Time = Pay)

• Key Words: "per hour" means multiply by hours worked

Tip 1: Always write down the formula before solving: Pay = Rate × Time.
Tip 2: Draw a timeline to visualize start and end times.
Tip 3: Account for breaks when calculating actual work time.
Tip 4: Practice with different hourly rates to build fluency.
Common errors: Forgetting to subtract break time, confusing multiplication with addition for pay calculations.
Success strategies: Draw timelines for time problems, use repeated addition to check multiplication.
Essential Formulas:

• Total Pay = Hourly Rate × Hours Worked

• Hours Worked = End Time - Start Time

• Actual Work Time = Total Time - Break Time

• Weekly Hours = Daily Hours × Days Per Week

• $1.00 = 100¢, Quarter = 25¢, Dime = 10¢, Nickel = 5¢, Penny = 1¢

Questions & Answers

Question: I don't understand how to calculate how much someone earns when they work multiple days. Can you explain?

Answer: To calculate earnings over multiple days, follow these steps:

  • First, find the total number of hours worked across all days
  • Then, multiply the hourly rate by the total hours

Example: $5 per hour, 4 hours per day, 3 days:

Step 1: Total hours = 4 hours/day × 3 days = 12 hours

Step 2: Total pay = $5/hour × 12 hours = $60

Or you can calculate daily pay first: $5 × 4 = $20 per day

Then multiply by days: $20 × 3 days = $60

Both methods give the same result!

Question: How do I calculate hours when someone takes a lunch break?

Answer: When calculating actual work hours, you need to subtract break time:

Steps to follow:

  • Find the total time from start to finish
  • Subtract any break time
  • The result is actual work time

Example: Work from 9 AM to 5 PM with 1-hour lunch:

Step 1: Total time = 5 PM - 9 AM = 8 hours

Step 2: Subtract break = 8 hours - 1 hour = 7 hours of actual work

So the person worked 7 hours, even though they were at work for 8 hours.

Remember: Lunch breaks don't count as work time!

Question: How can I check if my work math is correct?

Answer: Here are several ways to check your work math:

For pay calculations:

  • Check: Rate × Time = Pay
  • Example: $5/hour × 4 hours = $20
  • Check: $20 ÷ 4 hours = $5/hour

For time calculations:

  • Add up your hours to see if they match the total
  • Use a clock to visualize the time span
  • Estimate first: Does the answer seem reasonable?

Other verification tips:

  • Make sure units match (hours with hours, dollars with dollars)
  • Check that your answer makes sense in the real world
  • Try solving the problem a different way to confirm

This checking technique helps catch common errors!