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Finding the Fourth Proportional to 666.28, 919.40 and 404.28

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Solution

The fourth proportional to 666.28, 919.40 and 404.28 is: 557.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.28 : 919.40 = 404.28 : x
  2. Step 2: Convert to fraction form
    666.28/919.40 = 404.28/x
  3. Step 3: Cross multiply
    666.28x = 919.40 × 404.28
  4. Step 4: Simplify right side
    666.28x = 371,695.03
  5. Step 5: Solve for x
    x = 371,695.03/666.28
  6. Step 6: Final answer
    x = 557.87

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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.