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Finding the Fourth Proportional to 642.47, 886.68 and 406.42

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Solution

The fourth proportional to 642.47, 886.68 and 406.42 is: 560.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.47 : 886.68 = 406.42 : x
  2. Step 2: Convert to fraction form
    642.47/886.68 = 406.42/x
  3. Step 3: Cross multiply
    642.47x = 886.68 × 406.42
  4. Step 4: Simplify right side
    642.47x = 360,362.27
  5. Step 5: Solve for x
    x = 360,362.27/642.47
  6. Step 6: Final answer
    x = 560.91

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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.