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Finding the Fourth Proportional to 318.81, 440.07 and 308.55

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Solution

The fourth proportional to 318.81, 440.07 and 308.55 is: 425.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    318.81 : 440.07 = 308.55 : x
  2. Step 2: Convert to fraction form
    318.81/440.07 = 308.55/x
  3. Step 3: Cross multiply
    318.81x = 440.07 × 308.55
  4. Step 4: Simplify right side
    318.81x = 135,783.60
  5. Step 5: Solve for x
    x = 135,783.60/318.81
  6. Step 6: Final answer
    x = 425.91

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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.