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Finding the Fourth Proportional to 648.10, 972.15 and 440.20

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Solution

The fourth proportional to 648.10, 972.15 and 440.20 is: 660.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.10 : 972.15 = 440.20 : x
  2. Step 2: Convert to fraction form
    648.10/972.15 = 440.20/x
  3. Step 3: Cross multiply
    648.10x = 972.15 × 440.20
  4. Step 4: Simplify right side
    648.10x = 427,940.43
  5. Step 5: Solve for x
    x = 427,940.43/648.10
  6. Step 6: Final answer
    x = 660.30

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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.