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Finding the Fourth Proportional to 403.08, 555.81 and 318.91

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Solution

The fourth proportional to 403.08, 555.81 and 318.91 is: 439.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.08 : 555.81 = 318.91 : x
  2. Step 2: Convert to fraction form
    403.08/555.81 = 318.91/x
  3. Step 3: Cross multiply
    403.08x = 555.81 × 318.91
  4. Step 4: Simplify right side
    403.08x = 177,253.37
  5. Step 5: Solve for x
    x = 177,253.37/403.08
  6. Step 6: Final answer
    x = 439.75

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.