how can you subtract integers in real world problems

3 answers

Subtracting integers is a fundamental skill that can be applied in various real-world situations. Here are some common examples where you might encounter integer subtraction:

  1. Financial Transactions:

    • Imagine you have $50 in your bank account. If you spend $20, you would subtract that amount to find your new balance: 5020=30.
    • Conversely, if you had a debt of $30, it's like having 30. If you pay back that amount, your balance changes: 50(30)=50+30=80.
  2. Temperature Changes:

    • If today's temperature is 23 degrees Celsius, and it drops by 5 degrees, you can calculate the new temperature like this: 235=18.
    • If the temperature was at -2 degrees and it rises by 3 degrees, the calculation would be: 2(3)=2+3=1.
  3. Elevation Changes:

    • If you are at an elevation of 150 meters above sea level, and you descend 50 meters, you can find your new elevation by subtracting: 15050=100 meters.
    • If you start at -30 meters (below sea level) and rise 10 meters, you would calculate: 30(10)=30+10=20 meters.
  4. Scoring in Games:

    • In a game, if you have 80 points and lose 15 points for a penalty, you would find your new score as 8015=65.
    • If you are at a score of -10 points (perhaps due to penalties) and you gain 5 points, it would be 10(5)=10+5=5.
  5. Inventory Management:

    • Imagine a store has 200 items in stock. If 45 items are sold, the new inventory would be calculated as 20045=155.
    • If the inventory starts at -10 (indicating backorders), and 20 items come in, the calculation would be: 10(20)=10+20=10.
  6. Time Calculation:

    • If a movie starts at 7:30 PM and is 2 hours long, it ends at 7:30+2:00=9:30. Conversely, if it is rescheduled and the new start time is 9:00 PM, you could subtract to find out how late it starts: 9:007:30=1:30.

These examples illustrate how subtracting integers is a valuable skill across various contexts in everyday life. Each scenario involves determining how a quantity changes by subtracting one integer from another, helping you make informed decisions and understand situations better.

put it into one answer

Subtracting integers is useful in various real-world situations, including:

  1. Financial Transactions: If you have $50 and spend $20, your new balance is 5020=30. If you have a debt of $30 and pay it back, your balance changes to 50(30)=80.

  2. Temperature Changes: If it's 23 degrees Celsius and it drops by 5 degrees, the new temperature is 235=18. If it starts at -2 degrees and rises by 3 degrees, it calculates as 2(3)=1.

  3. Elevation Changes: Starting at 150 meters above sea level and descending 50 meters results in a new elevation of 15050=100 meters. If you start at -30 meters (below sea level) and rise 10 meters, the elevation is 30(10)=20 meters.

  4. Scoring in Games: You have 80 points and lose 15 for a penalty, so your score becomes 8015=65. Starting at -10 due to penalties and gaining 5 points would mean a score of 10(5)=5.

  5. Inventory Management: A store with 200 items in stock that sells 45 has 20045=155 left. If starting at -10 (backorders) and receiving 20 items, the inventory changes to 10(20)=10.

  6. Time Calculation: A movie starts at 7:30 PM and runs for 2 hours, ending at 9:30. If rescheduled to start at 9:00 PM, the delay can be calculated as 9:007:30=1:30.

In each case, subtracting integers helps manage changes and make informed decisions in everyday life.