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Finding the Fourth Proportional to 390.30, 539.13 and 325.14

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Solution

The fourth proportional to 390.30, 539.13 and 325.14 is: 449.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.30 : 539.13 = 325.14 : x
  2. Step 2: Convert to fraction form
    390.30/539.13 = 325.14/x
  3. Step 3: Cross multiply
    390.30x = 539.13 × 325.14
  4. Step 4: Simplify right side
    390.30x = 175,292.73
  5. Step 5: Solve for x
    x = 175,292.73/390.30
  6. Step 6: Final answer
    x = 449.12

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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.