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Finding the Fourth Proportional to 338.08, 509.42 and 278.54

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Solution

The fourth proportional to 338.08, 509.42 and 278.54 is: 419.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.08 : 509.42 = 278.54 : x
  2. Step 2: Convert to fraction form
    338.08/509.42 = 278.54/x
  3. Step 3: Cross multiply
    338.08x = 509.42 × 278.54
  4. Step 4: Simplify right side
    338.08x = 141,893.85
  5. Step 5: Solve for x
    x = 141,893.85/338.08
  6. Step 6: Final answer
    x = 419.70

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.