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Finding the Fourth Proportional to 487.80, 731.58 and 213.83

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Solution

The fourth proportional to 487.80, 731.58 and 213.83 is: 320.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.80 : 731.58 = 213.83 : x
  2. Step 2: Convert to fraction form
    487.80/731.58 = 213.83/x
  3. Step 3: Cross multiply
    487.80x = 731.58 × 213.83
  4. Step 4: Simplify right side
    487.80x = 156,430.09
  5. Step 5: Solve for x
    x = 156,430.09/487.80
  6. Step 6: Final answer
    x = 320.68

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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.