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Finding the Fourth Proportional to 414.40, 620.40 and 318.40

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Solution

The fourth proportional to 414.40, 620.40 and 318.40 is: 476.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    414.40 : 620.40 = 318.40 : x
  2. Step 2: Convert to fraction form
    414.40/620.40 = 318.40/x
  3. Step 3: Cross multiply
    414.40x = 620.40 × 318.40
  4. Step 4: Simplify right side
    414.40x = 197,535.36
  5. Step 5: Solve for x
    x = 197,535.36/414.40
  6. Step 6: Final answer
    x = 476.68

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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.