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Finding the Fourth Proportional to 643.78, 887.54 and 550.12

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Solution

The fourth proportional to 643.78, 887.54 and 550.12 is: 758.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.78 : 887.54 = 550.12 : x
  2. Step 2: Convert to fraction form
    643.78/887.54 = 550.12/x
  3. Step 3: Cross multiply
    643.78x = 887.54 × 550.12
  4. Step 4: Simplify right side
    643.78x = 488,253.50
  5. Step 5: Solve for x
    x = 488,253.50/643.78
  6. Step 6: Final answer
    x = 758.42

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1.5x scale

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.