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Finding the Fourth Proportional to 338.96, 509.58 and 278.56

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Solution

The fourth proportional to 338.96, 509.58 and 278.56 is: 418.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.96 : 509.58 = 278.56 : x
  2. Step 2: Convert to fraction form
    338.96/509.58 = 278.56/x
  3. Step 3: Cross multiply
    338.96x = 509.58 × 278.56
  4. Step 4: Simplify right side
    338.96x = 141,948.60
  5. Step 5: Solve for x
    x = 141,948.60/338.96
  6. Step 6: Final answer
    x = 418.78

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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.