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Finding the Fourth Proportional to 411.15, 618.71 and 338.56

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Solution

The fourth proportional to 411.15, 618.71 and 338.56 is: 509.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    411.15 : 618.71 = 338.56 : x
  2. Step 2: Convert to fraction form
    411.15/618.71 = 338.56/x
  3. Step 3: Cross multiply
    411.15x = 618.71 × 338.56
  4. Step 4: Simplify right side
    411.15x = 209,470.46
  5. Step 5: Solve for x
    x = 209,470.46/411.15
  6. Step 6: Final answer
    x = 509.47

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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.