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Finding the Fourth Proportional to 487.89, 731.43 and 391.50

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Solution

The fourth proportional to 487.89, 731.43 and 391.50 is: 586.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.89 : 731.43 = 391.50 : x
  2. Step 2: Convert to fraction form
    487.89/731.43 = 391.50/x
  3. Step 3: Cross multiply
    487.89x = 731.43 × 391.50
  4. Step 4: Simplify right side
    487.89x = 286,354.85
  5. Step 5: Solve for x
    x = 286,354.85/487.89
  6. Step 6: Final answer
    x = 586.93

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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.