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Finding the Fourth Proportional to 580.20, 869.68 and 287.40

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Solution

The fourth proportional to 580.20, 869.68 and 287.40 is: 430.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    580.20 : 869.68 = 287.40 : x
  2. Step 2: Convert to fraction form
    580.20/869.68 = 287.40/x
  3. Step 3: Cross multiply
    580.20x = 869.68 × 287.40
  4. Step 4: Simplify right side
    580.20x = 249,946.03
  5. Step 5: Solve for x
    x = 249,946.03/580.20
  6. Step 6: Final answer
    x = 430.79

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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.