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Finding the Fourth Proportional to 390.07, 585.39 and 387.02

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Solution

The fourth proportional to 390.07, 585.39 and 387.02 is: 580.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.07 : 585.39 = 387.02 : x
  2. Step 2: Convert to fraction form
    390.07/585.39 = 387.02/x
  3. Step 3: Cross multiply
    390.07x = 585.39 × 387.02
  4. Step 4: Simplify right side
    390.07x = 226,557.64
  5. Step 5: Solve for x
    x = 226,557.64/390.07
  6. Step 6: Final answer
    x = 580.82

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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.