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Finding the Fourth Proportional to 339.81, 509.90 and 218.31

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Solution

The fourth proportional to 339.81, 509.90 and 218.31 is: 327.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.81 : 509.90 = 218.31 : x
  2. Step 2: Convert to fraction form
    339.81/509.90 = 218.31/x
  3. Step 3: Cross multiply
    339.81x = 509.90 × 218.31
  4. Step 4: Simplify right side
    339.81x = 111,315.18
  5. Step 5: Solve for x
    x = 111,315.18/339.81
  6. Step 6: Final answer
    x = 327.58

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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.