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Finding the Fourth Proportional to 665.90, 919.05 and 404.10

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Solution

The fourth proportional to 665.90, 919.05 and 404.10 is: 557.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.90 : 919.05 = 404.10 : x
  2. Step 2: Convert to fraction form
    665.90/919.05 = 404.10/x
  3. Step 3: Cross multiply
    665.90x = 919.05 × 404.10
  4. Step 4: Simplify right side
    665.90x = 371,388.11
  5. Step 5: Solve for x
    x = 371,388.11/665.90
  6. Step 6: Final answer
    x = 557.72

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.