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Finding the Fourth Proportional to 390.20, 585.21 and 130.14

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Solution

The fourth proportional to 390.20, 585.21 and 130.14 is: 195.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.20 : 585.21 = 130.14 : x
  2. Step 2: Convert to fraction form
    390.20/585.21 = 130.14/x
  3. Step 3: Cross multiply
    390.20x = 585.21 × 130.14
  4. Step 4: Simplify right side
    390.20x = 76,156.55
  5. Step 5: Solve for x
    x = 76,156.55/390.20
  6. Step 6: Final answer
    x = 195.18

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.