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Finding the Fourth Proportional to 458.90, 688.13 and 215.30

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Solution

The fourth proportional to 458.90, 688.13 and 215.30 is: 322.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.90 : 688.13 = 215.30 : x
  2. Step 2: Convert to fraction form
    458.90/688.13 = 215.30/x
  3. Step 3: Cross multiply
    458.90x = 688.13 × 215.30
  4. Step 4: Simplify right side
    458.90x = 148,154.39
  5. Step 5: Solve for x
    x = 148,154.39/458.90
  6. Step 6: Final answer
    x = 322.85

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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.