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Finding the Fourth Proportional to 258.55, 389.98 and 258.55

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Solution

The fourth proportional to 258.55, 389.98 and 258.55 is: 389.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.55 : 389.98 = 258.55 : x
  2. Step 2: Convert to fraction form
    258.55/389.98 = 258.55/x
  3. Step 3: Cross multiply
    258.55x = 389.98 × 258.55
  4. Step 4: Simplify right side
    258.55x = 100,829.33
  5. Step 5: Solve for x
    x = 100,829.33/258.55
  6. Step 6: Final answer
    x = 389.98

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.