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Finding the Fourth Proportional to 400.60, 601.80 and 385.30

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Solution

The fourth proportional to 400.60, 601.80 and 385.30 is: 578.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.60 : 601.80 = 385.30 : x
  2. Step 2: Convert to fraction form
    400.60/601.80 = 385.30/x
  3. Step 3: Cross multiply
    400.60x = 601.80 × 385.30
  4. Step 4: Simplify right side
    400.60x = 231,873.54
  5. Step 5: Solve for x
    x = 231,873.54/400.60
  6. Step 6: Final answer
    x = 578.82

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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.