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Finding the Fourth Proportional to 390.20, 585.18 and 268.16

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Solution

The fourth proportional to 390.20, 585.18 and 268.16 is: 402.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.20 : 585.18 = 268.16 : x
  2. Step 2: Convert to fraction form
    390.20/585.18 = 268.16/x
  3. Step 3: Cross multiply
    390.20x = 585.18 × 268.16
  4. Step 4: Simplify right side
    390.20x = 156,921.87
  5. Step 5: Solve for x
    x = 156,921.87/390.20
  6. Step 6: Final answer
    x = 402.16

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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.