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Finding the Fourth Proportional to 648.40, 972.60 and 618.70

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Solution

The fourth proportional to 648.40, 972.60 and 618.70 is: 928.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.40 : 972.60 = 618.70 : x
  2. Step 2: Convert to fraction form
    648.40/972.60 = 618.70/x
  3. Step 3: Cross multiply
    648.40x = 972.60 × 618.70
  4. Step 4: Simplify right side
    648.40x = 601,747.62
  5. Step 5: Solve for x
    x = 601,747.62/648.40
  6. Step 6: Final answer
    x = 928.05

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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.