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Finding the Fourth Proportional to 610.80, 842.84 and 389.92

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Solution

The fourth proportional to 610.80, 842.84 and 389.92 is: 538.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    610.80 : 842.84 = 389.92 : x
  2. Step 2: Convert to fraction form
    610.80/842.84 = 389.92/x
  3. Step 3: Cross multiply
    610.80x = 842.84 × 389.92
  4. Step 4: Simplify right side
    610.80x = 328,640.17
  5. Step 5: Solve for x
    x = 328,640.17/610.80
  6. Step 6: Final answer
    x = 538.05

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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.