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Finding the Fourth Proportional to 666.78, 919.57 and 417.82

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Solution

The fourth proportional to 666.78, 919.57 and 417.82 is: 576.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.78 : 919.57 = 417.82 : x
  2. Step 2: Convert to fraction form
    666.78/919.57 = 417.82/x
  3. Step 3: Cross multiply
    666.78x = 919.57 × 417.82
  4. Step 4: Simplify right side
    666.78x = 384,214.74
  5. Step 5: Solve for x
    x = 384,214.74/666.78
  6. Step 6: Final answer
    x = 576.22

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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.