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Finding the Fourth Proportional to 610.90, 842.37 and 389.50

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Solution

The fourth proportional to 610.90, 842.37 and 389.50 is: 537.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    610.90 : 842.37 = 389.50 : x
  2. Step 2: Convert to fraction form
    610.90/842.37 = 389.50/x
  3. Step 3: Cross multiply
    610.90x = 842.37 × 389.50
  4. Step 4: Simplify right side
    610.90x = 328,103.12
  5. Step 5: Solve for x
    x = 328,103.12/610.90
  6. Step 6: Final answer
    x = 537.08

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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.