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Finding the Fourth Proportional to 390.18, 582.20 and 349.32

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Solution

The fourth proportional to 390.18, 582.20 and 349.32 is: 521.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.18 : 582.20 = 349.32 : x
  2. Step 2: Convert to fraction form
    390.18/582.20 = 349.32/x
  3. Step 3: Cross multiply
    390.18x = 582.20 × 349.32
  4. Step 4: Simplify right side
    390.18x = 203,374.10
  5. Step 5: Solve for x
    x = 203,374.10/390.18
  6. Step 6: Final answer
    x = 521.23

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.