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Finding the Fourth Proportional to 438.90, 605.12 and 308.09

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Solution

The fourth proportional to 438.90, 605.12 and 308.09 is: 424.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.90 : 605.12 = 308.09 : x
  2. Step 2: Convert to fraction form
    438.90/605.12 = 308.09/x
  3. Step 3: Cross multiply
    438.90x = 605.12 × 308.09
  4. Step 4: Simplify right side
    438.90x = 186,426.85
  5. Step 5: Solve for x
    x = 186,426.85/438.90
  6. Step 6: Final answer
    x = 424.76

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.