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Finding the Fourth Proportional to 258.39, 390.02 and 258.39

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Solution

The fourth proportional to 258.39, 390.02 and 258.39 is: 390.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.39 : 390.02 = 258.39 : x
  2. Step 2: Convert to fraction form
    258.39/390.02 = 258.39/x
  3. Step 3: Cross multiply
    258.39x = 390.02 × 258.39
  4. Step 4: Simplify right side
    258.39x = 100,775.98
  5. Step 5: Solve for x
    x = 100,775.98/258.39
  6. Step 6: Final answer
    x = 390.02

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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.