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Finding the Fourth Proportional to 438.42, 605.09 and 305.85

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Solution

The fourth proportional to 438.42, 605.09 and 305.85 is: 422.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.42 : 605.09 = 305.85 : x
  2. Step 2: Convert to fraction form
    438.42/605.09 = 305.85/x
  3. Step 3: Cross multiply
    438.42x = 605.09 × 305.85
  4. Step 4: Simplify right side
    438.42x = 185,066.78
  5. Step 5: Solve for x
    x = 185,066.78/438.42
  6. Step 6: Final answer
    x = 422.12

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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.