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Finding the Fourth Proportional to 643.07, 886.55 and 406.90

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Solution

The fourth proportional to 643.07, 886.55 and 406.90 is: 560.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.07 : 886.55 = 406.90 : x
  2. Step 2: Convert to fraction form
    643.07/886.55 = 406.90/x
  3. Step 3: Cross multiply
    643.07x = 886.55 × 406.90
  4. Step 4: Simplify right side
    643.07x = 360,737.20
  5. Step 5: Solve for x
    x = 360,737.20/643.07
  6. Step 6: Final answer
    x = 560.96

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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.