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Finding the Fourth Proportional to 643.85, 886.20 and 550.28

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Solution

The fourth proportional to 643.85, 886.20 and 550.28 is: 757.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.85 : 886.20 = 550.28 : x
  2. Step 2: Convert to fraction form
    643.85/886.20 = 550.28/x
  3. Step 3: Cross multiply
    643.85x = 886.20 × 550.28
  4. Step 4: Simplify right side
    643.85x = 487,658.14
  5. Step 5: Solve for x
    x = 487,658.14/643.85
  6. Step 6: Final answer
    x = 757.41

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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.