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Finding the Fourth Proportional to 390.38, 538.28 and 291.97

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Solution

The fourth proportional to 390.38, 538.28 and 291.97 is: 402.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.38 : 538.28 = 291.97 : x
  2. Step 2: Convert to fraction form
    390.38/538.28 = 291.97/x
  3. Step 3: Cross multiply
    390.38x = 538.28 × 291.97
  4. Step 4: Simplify right side
    390.38x = 157,161.61
  5. Step 5: Solve for x
    x = 157,161.61/390.38
  6. Step 6: Final answer
    x = 402.59

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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.