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Finding the Fourth Proportional to 658.64, 988.92 and 647.72

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Solution

The fourth proportional to 658.64, 988.92 and 647.72 is: 972.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.64 : 988.92 = 647.72 : x
  2. Step 2: Convert to fraction form
    658.64/988.92 = 647.72/x
  3. Step 3: Cross multiply
    658.64x = 988.92 × 647.72
  4. Step 4: Simplify right side
    658.64x = 640,543.26
  5. Step 5: Solve for x
    x = 640,543.26/658.64
  6. Step 6: Final answer
    x = 972.52

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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.