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Finding the Fourth Proportional to 610.78, 842.99 and 389.68

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Solution

The fourth proportional to 610.78, 842.99 and 389.68 is: 537.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    610.78 : 842.99 = 389.68 : x
  2. Step 2: Convert to fraction form
    610.78/842.99 = 389.68/x
  3. Step 3: Cross multiply
    610.78x = 842.99 × 389.68
  4. Step 4: Simplify right side
    610.78x = 328,496.34
  5. Step 5: Solve for x
    x = 328,496.34/610.78
  6. Step 6: Final answer
    x = 537.83

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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.