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Finding the Fourth Proportional to 386.31, 579.32 and 239.84

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Solution

The fourth proportional to 386.31, 579.32 and 239.84 is: 359.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.31 : 579.32 = 239.84 : x
  2. Step 2: Convert to fraction form
    386.31/579.32 = 239.84/x
  3. Step 3: Cross multiply
    386.31x = 579.32 × 239.84
  4. Step 4: Simplify right side
    386.31x = 138,946.34
  5. Step 5: Solve for x
    x = 138,946.34/386.31
  6. Step 6: Final answer
    x = 359.68

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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.