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Finding the Fourth Proportional to 648.60, 971.28 and 455.28

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Solution

The fourth proportional to 648.60, 971.28 and 455.28 is: 681.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.60 : 971.28 = 455.28 : x
  2. Step 2: Convert to fraction form
    648.60/971.28 = 455.28/x
  3. Step 3: Cross multiply
    648.60x = 971.28 × 455.28
  4. Step 4: Simplify right side
    648.60x = 442,204.36
  5. Step 5: Solve for x
    x = 442,204.36/648.60
  6. Step 6: Final answer
    x = 681.78

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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.