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Finding the Fourth Proportional to 338.95, 509.55 and 278.53

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Solution

The fourth proportional to 338.95, 509.55 and 278.53 is: 418.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.95 : 509.55 = 278.53 : x
  2. Step 2: Convert to fraction form
    338.95/509.55 = 278.53/x
  3. Step 3: Cross multiply
    338.95x = 509.55 × 278.53
  4. Step 4: Simplify right side
    338.95x = 141,924.96
  5. Step 5: Solve for x
    x = 141,924.96/338.95
  6. Step 6: Final answer
    x = 418.72

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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.