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Finding the Fourth Proportional to 620.00, 855.49 and 398.93

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Solution

The fourth proportional to 620.00, 855.49 and 398.93 is: 550.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.00 : 855.49 = 398.93 : x
  2. Step 2: Convert to fraction form
    620.00/855.49 = 398.93/x
  3. Step 3: Cross multiply
    620.00x = 855.49 × 398.93
  4. Step 4: Simplify right side
    620.00x = 341,274.98
  5. Step 5: Solve for x
    x = 341,274.98/620.00
  6. Step 6: Final answer
    x = 550.44

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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.