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Finding the Fourth Proportional to 390.91, 539.54 and 235.75

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Solution

The fourth proportional to 390.91, 539.54 and 235.75 is: 325.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.91 : 539.54 = 235.75 : x
  2. Step 2: Convert to fraction form
    390.91/539.54 = 235.75/x
  3. Step 3: Cross multiply
    390.91x = 539.54 × 235.75
  4. Step 4: Simplify right side
    390.91x = 127,196.56
  5. Step 5: Solve for x
    x = 127,196.56/390.91
  6. Step 6: Final answer
    x = 325.39

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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.