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Finding the Fourth Proportional to 339.20, 509.10 and 290.60

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Solution

The fourth proportional to 339.20, 509.10 and 290.60 is: 436.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.20 : 509.10 = 290.60 : x
  2. Step 2: Convert to fraction form
    339.20/509.10 = 290.60/x
  3. Step 3: Cross multiply
    339.20x = 509.10 × 290.60
  4. Step 4: Simplify right side
    339.20x = 147,944.46
  5. Step 5: Solve for x
    x = 147,944.46/339.20
  6. Step 6: Final answer
    x = 436.16

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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.