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Finding the Fourth Proportional to 658.64, 987 and 628.40

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Solution

The fourth proportional to 658.64, 987 and 628.40 is: 941.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.64 : 987 = 628.40 : x
  2. Step 2: Convert to fraction form
    658.64/987 = 628.40/x
  3. Step 3: Cross multiply
    658.64x = 987 × 628.40
  4. Step 4: Simplify right side
    658.64x = 620,230.80
  5. Step 5: Solve for x
    x = 620,230.80/658.64
  6. Step 6: Final answer
    x = 941.68

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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.