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Finding the Fourth Proportional to 658.90, 909 and 422.80

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Solution

The fourth proportional to 658.90, 909 and 422.80 is: 583.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.90 : 909 = 422.80 : x
  2. Step 2: Convert to fraction form
    658.90/909 = 422.80/x
  3. Step 3: Cross multiply
    658.90x = 909 × 422.80
  4. Step 4: Simplify right side
    658.90x = 384,322.93
  5. Step 5: Solve for x
    x = 384,322.93/658.90
  6. Step 6: Final answer
    x = 583.28

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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.