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Finding the Fourth Proportional to 400.90, 600.69 and 385.91

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Solution

The fourth proportional to 400.90, 600.69 and 385.91 is: 578.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.90 : 600.69 = 385.91 : x
  2. Step 2: Convert to fraction form
    400.90/600.69 = 385.91/x
  3. Step 3: Cross multiply
    400.90x = 600.69 × 385.91
  4. Step 4: Simplify right side
    400.90x = 231,812.28
  5. Step 5: Solve for x
    x = 231,812.28/400.90
  6. Step 6: Final answer
    x = 578.23

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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.