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Finding the Fourth Proportional to 666.25, 919.28 and 404.21

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Solution

The fourth proportional to 666.25, 919.28 and 404.21 is: 557.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.25 : 919.28 = 404.21 : x
  2. Step 2: Convert to fraction form
    666.25/919.28 = 404.21/x
  3. Step 3: Cross multiply
    666.25x = 919.28 × 404.21
  4. Step 4: Simplify right side
    666.25x = 371,585.48
  5. Step 5: Solve for x
    x = 371,585.48/666.25
  6. Step 6: Final answer
    x = 557.73

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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.