Solving Real-World Application Problems 6-1

Sep 28, 2024

Lecture Notes: Application Problems in Guided Notes

Overview

  • Discussed application problems from the guided notes.
  • Focused on using algebraic methods to solve problems with unknowns.

Problem 15: Baseball Teams Contract Offer

  • Objective: Determine the first team's offer for a pitcher.
  • Given:
    • Second team offers double the first team's offer plus an extra million per year.
    • Player seeks $18 million per year.
  • Solution:
    • Let X be the first team's offer.
    • Equation: 2X + 1 = 18.
    • Solve:
      • Subtract 1: 2X = 17.
      • Divide by 2: X = 8.5.
    • Conclusion: First team's offer was $8.5 million.

Problem 16A: Heights of Donna and Christina

  • Objective: Represent Donna's and Christina's heights.
  • Given:
    • Donna is 5 inches taller than Christina.
  • Solution:
    • Let X represent Christina's height.
    • Donna's height: X + 5.

Problem 16B: Test Grades of Ariana and John

  • Objective: Express John's test grade.
  • Given:
    • John's grade is 5 points less than twice Ariana's.
  • Solution:
    • Let X be Ariana's grade.
    • John's grade: 2X - 5.

Problem 17: Cutting a Board

  • Objective: Find lengths of two pieces.
  • Given:
    • Board is 6 feet long.
    • One piece is 3 times longer than the other.
  • Solution:
    • Let X be the shorter piece.
    • Longer piece: 3X.
    • Equation: X + 3X = 6.
    • Solve:
      • 4X = 6.
      • X = 1.5 feet.
    • Results: Shorter piece = 1.5 ft, Longer piece = 4.5 ft.

Problem 18: Support Post Heights

  • Objective: Determine heights of support posts.
  • Given:
    • Deck height is 92 inches.
    • Taller post is 8 inches longer than the shorter one.
  • Solution:
    • Let X be the shorter post.
    • Taller post: X + 8.
    • Equation: 2X + 8 = 92.
    • Solve:
      • Subtract 8: 2X = 84.
      • Divide by 2: X = 42 inches.
    • Results: Shorter = 42 in, Taller = 50 in.

Problem 19: Tips in Bills

  • Objective: Find the number of $1 and $5 bills.
  • Given:
    • Total tips: $137
    • 53 more $1 bills than $5 bills.
  • Solution:
    • Method 1: Trial and Error
      • Test different combinations of bills.
      • Approach: Adjust number of $5 bills to match total.
    • Method 2: Algebraic Solution
      • Let X be the number of $5 bills.
      • Number of $1 bills: X + 53.
      • Equation: 5X + (X + 53) = 137.
      • Simplify and solve:
        • 6X + 53 = 137
        • 6X = 84
        • X = 14
      • Results: 14 $5 bills, 67 $1 bills.

Conclusion

  • Emphasis on using algebraic equations to simplify problem-solving.
  • Highlighted both trial/error and algebraic strategies to approach real-world problems.