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Finding the Fourth Proportional to 390.38, 538.49 and 248.54

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Solution

The fourth proportional to 390.38, 538.49 and 248.54 is: 342.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.38 : 538.49 = 248.54 : x
  2. Step 2: Convert to fraction form
    390.38/538.49 = 248.54/x
  3. Step 3: Cross multiply
    390.38x = 538.49 × 248.54
  4. Step 4: Simplify right side
    390.38x = 133,836.30
  5. Step 5: Solve for x
    x = 133,836.30/390.38
  6. Step 6: Final answer
    x = 342.84

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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.