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Finding the Fourth Proportional to 339.88, 509.64 and 218.20

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Solution

The fourth proportional to 339.88, 509.64 and 218.20 is: 327.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.88 : 509.64 = 218.20 : x
  2. Step 2: Convert to fraction form
    339.88/509.64 = 218.20/x
  3. Step 3: Cross multiply
    339.88x = 509.64 × 218.20
  4. Step 4: Simplify right side
    339.88x = 111,203.45
  5. Step 5: Solve for x
    x = 111,203.45/339.88
  6. Step 6: Final answer
    x = 327.18

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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.