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Finding the Fourth Proportional to 647.00, 892.89 and 398.58

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Solution

The fourth proportional to 647.00, 892.89 and 398.58 is: 550.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.00 : 892.89 = 398.58 : x
  2. Step 2: Convert to fraction form
    647.00/892.89 = 398.58/x
  3. Step 3: Cross multiply
    647.00x = 892.89 × 398.58
  4. Step 4: Simplify right side
    647.00x = 355,888.10
  5. Step 5: Solve for x
    x = 355,888.10/647.00
  6. Step 6: Final answer
    x = 550.06

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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.