Home / 3,989.40-5,981.40-2,115.60

Finding the Fourth Proportional to 3,989.40, 5,981.40 and 2,115.60

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Solution

The fourth proportional to 3,989.40, 5,981.40 and 2,115.60 is: 3,171.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,989.40 : 5,981.40 = 2,115.60 : x
  2. Step 2: Convert to fraction form
    3,989.40/5,981.40 = 2,115.60/x
  3. Step 3: Cross multiply
    3,989.40x = 5,981.40 × 2,115.60
  4. Step 4: Simplify right side
    3,989.40x = 12,654,249.84
  5. Step 5: Solve for x
    x = 12,654,249.84/3,989.40
  6. Step 6: Final answer
    x = 3,171.97

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.