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Finding the Fourth Proportional to 487.80, 731.06 and 213.59

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Solution

The fourth proportional to 487.80, 731.06 and 213.59 is: 320.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.80 : 731.06 = 213.59 : x
  2. Step 2: Convert to fraction form
    487.80/731.06 = 213.59/x
  3. Step 3: Cross multiply
    487.80x = 731.06 × 213.59
  4. Step 4: Simplify right side
    487.80x = 156,142.38
  5. Step 5: Solve for x
    x = 156,142.38/487.80
  6. Step 6: Final answer
    x = 320.10

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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.