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Finding the Fourth Proportional to 618.70, 928.05 and 424.30

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Solution

The fourth proportional to 618.70, 928.05 and 424.30 is: 636.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.70 : 928.05 = 424.30 : x
  2. Step 2: Convert to fraction form
    618.70/928.05 = 424.30/x
  3. Step 3: Cross multiply
    618.70x = 928.05 × 424.30
  4. Step 4: Simplify right side
    618.70x = 393,771.62
  5. Step 5: Solve for x
    x = 393,771.62/618.70
  6. Step 6: Final answer
    x = 636.45

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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.